From 1fd57f925a48a3835618f350fcae190929652f1a Mon Sep 17 00:00:00 2001
From: Javier <10879637+javiertuya@users.noreply.github.com>
Date: Sun, 11 Aug 2024 10:53:14 +0200
Subject: [PATCH] Mutation evaluation, java only

---
 .../Giis.Qacover.Driver/QueryReader.N.cs      |  46 ++++++++
 .../Giis.Qacover.Driver/StatementAdapter.N.cs |  19 +---
 .../Configuration.cs                          |  14 +++
 .../RuleServices.cs                           |  14 ++-
 .../Giis.Qacover.Core/CoverageManager.cs      |   2 +
 .../Giis.Qacover.Core/IQueryReader.cs         |  24 ++++
 .../Giis.Qacover.Core/QueryStatement.cs       |  63 +----------
 .../Giis.Qacover.Core/RuleDriver.cs           |   6 +
 .../Giis.Qacover.Core/RuleDriverFactory.cs    |  11 +-
 .../Giis.Qacover.Core/RuleDriverFpc.cs        |   9 +-
 .../Giis.Qacover.Core/RuleDriverMutation.cs   |  34 ++++++
 .../Giis.Qacover.Report/ClassHtmlWriter.cs    |   4 +-
 .../Test4giis.Qacover/TestFaults.cs           |   8 +-
 net/build.xml                                 |   1 +
 .../qacover-report/all-data-by-run-order.txt  |  14 +--
 net/resources/qacover-report/index.html       |   2 +-
 .../test4giis.qacoverapp.AppSimpleJdbc.html   |   2 +-
 .../test4giis.qacoverapp.AppSimpleJdbc2.html  |   2 +-
 ...4giis.qacoverapp.AppSimpleJdbc3Errors.html |   8 +-
 .../giis/qacover/core/CoverageManager.java    |   6 +-
 .../java/giis/qacover/core/IQueryReader.java  |  26 +++++
 .../giis/qacover/core/QueryStatement.java     |  43 +------
 .../java/giis/qacover/core/RuleDriver.java    |   6 +
 .../giis/qacover/core/RuleDriverFactory.java  |   7 +-
 .../java/giis/qacover/core/RuleDriverFpc.java |   9 +-
 .../giis/qacover/core/RuleDriverMutation.java |  32 ++++++
 .../qacover/core/services/Configuration.java  |   9 ++
 .../qacover/core/services/RuleServices.java   |  11 +-
 .../java/giis/qacover/driver/QueryReader.java |  91 +++++++++++++++
 .../giis/qacover/driver/StatementAdapter.java |   5 +
 .../java/test4giis/qacover/TestFaults.java    |  12 +-
 .../qacover/TestMutationEvaluation.java       | 105 ++++++++++++++++++
 .../java/test4giis/qacoverapp/AppBase.java    |   9 ++
 .../qacover-report/all-data-by-run-order.txt  |  14 +--
 ...4giis.qacoverapp.AppSimpleJdbc3Errors.html |   6 +-
 .../giis/qacover/report/ClassHtmlWriter.java  |   6 +-
 36 files changed, 517 insertions(+), 163 deletions(-)
 create mode 100644 net/QACover/Giis.Qacover.Driver/QueryReader.N.cs
 create mode 100644 net/QACover/Translated/Giis.Qacover.Core/IQueryReader.cs
 create mode 100644 net/QACover/Translated/Giis.Qacover.Core/RuleDriverMutation.cs
 create mode 100644 qacover-core/src/main/java/giis/qacover/core/IQueryReader.java
 create mode 100644 qacover-core/src/main/java/giis/qacover/core/RuleDriverMutation.java
 create mode 100644 qacover-core/src/main/java/giis/qacover/driver/QueryReader.java
 create mode 100644 qacover-core/src/test/java/test4giis/qacover/TestMutationEvaluation.java

diff --git a/net/QACover/Giis.Qacover.Driver/QueryReader.N.cs b/net/QACover/Giis.Qacover.Driver/QueryReader.N.cs
new file mode 100644
index 0000000..a85ce0e
--- /dev/null
+++ b/net/QACover/Giis.Qacover.Driver/QueryReader.N.cs
@@ -0,0 +1,46 @@
+using Giis.Qacover.Core;
+using Giis.Qacover.Portable;
+using System;
+using System.Collections.Generic;
+using System.Data.Common;
+
+namespace Giis.Qacover.Driver
+{
+    public class QueryReader : IQueryReader
+    {
+        DbCommand cmd;
+
+        // This implementation does not takes a connection and sql,
+        // included both and was created by the StatementAdapter
+        // because the way in which parameters were replaced
+        public QueryReader(DbCommand cmd)
+        {
+            this.cmd = cmd;
+        }
+        public bool HasRows()
+        {
+            try
+            {
+                DbDataReader reader = cmd.ExecuteReader();
+                bool hasNext = reader.Read();
+                reader.Close();
+                return hasNext;
+            }
+            catch (Exception e) // just to produce same exception than java version
+            {
+                throw new QaCoverException("QueryReader.hasRows", e);
+            }
+        }
+
+        public IList<string[]> GetRows()
+        {
+            throw new System.NotImplementedException();
+        }
+
+        public bool EqualRows(IList<string[]> expected)
+        {
+            throw new System.NotImplementedException();
+        }
+
+    }
+}
\ No newline at end of file
diff --git a/net/QACover/Giis.Qacover.Driver/StatementAdapter.N.cs b/net/QACover/Giis.Qacover.Driver/StatementAdapter.N.cs
index 458c83d..59127e1 100644
--- a/net/QACover/Giis.Qacover.Driver/StatementAdapter.N.cs
+++ b/net/QACover/Giis.Qacover.Driver/StatementAdapter.N.cs
@@ -64,13 +64,9 @@ public override Connection GetConnection()
         {
             return new Connection(nativeConn);
         }
-        /**
-         * Determina si la ejecucion del sql devuelve alguna fila (usada para evaluar reglas fpc)
-         */
-        public override bool HasRows(string sql)
+
+        public override IQueryReader GetQueryReader(String sql)
         {
-            try
-            {
                 DbCommand cmd = this.nativeConn.CreateCommand();
                 //El remplazo de parametros tiene tres situaciones:
                 //-no hay parametros
@@ -86,15 +82,7 @@ public override bool HasRows(string sql)
                 else if (this.parameters != null && this.parameters.Size() > 0)
                     cmd.CommandText = GetSqlWithValues(sql);
 
-                DbDataReader reader = cmd.ExecuteReader();
-                bool hasNext = reader.Read();
-                reader.Close();
-                return hasNext;
-            }
-            catch (Exception e)
-            {
-                throw new QaCoverException("SpyStatementAdapter.hasRows", e);
-            }
+                return new QueryReader(cmd);
         }
         private void AddParameters(DbCommand cmd, DbParameterCollection parameters)
         {
@@ -114,6 +102,7 @@ private void AddParameters(DbCommand cmd, DbParameterCollection parameters)
                     cmd.Parameters.Add(param);
             }
         }
+
     }
 
 }
diff --git a/net/QACover/Translated/Giis.Qacover.Core.Services/Configuration.cs b/net/QACover/Translated/Giis.Qacover.Core.Services/Configuration.cs
index 0f2fcc5..7cd0c90 100644
--- a/net/QACover/Translated/Giis.Qacover.Core.Services/Configuration.cs
+++ b/net/QACover/Translated/Giis.Qacover.Core.Services/Configuration.cs
@@ -33,6 +33,8 @@ public class Configuration
 
 		private string storeReportsLocation;
 
+		private string ruleServiceType;
+
 		private string fpcServiceUrl;
 
 		private string fpcServiceOptions;
@@ -77,6 +79,7 @@ public virtual Giis.Qacover.Core.Services.Configuration Reset()
 			string defaultReportsSubDir = FileUtil.GetPath(Parameters.GetReportSubdir(), QacoverName, "reports");
 			storeRulesLocation = FileUtil.GetPath(storeRootLocation, GetProperty("qacover.store.rules", defaultRulesSubDir));
 			storeReportsLocation = FileUtil.GetPath(storeRootLocation, GetProperty("qacover.store.reports", defaultReportsSubDir));
+			ruleServiceType = "fpc";
 			fpcServiceUrl = GetProperty("qacover.fpc.url", "https://in2test.lsi.uniovi.es/tdrules/api/v4");
 			fpcServiceOptions = GetProperty("qacover.fpc.options", string.Empty);
 			optimizeRuleEvaluation = JavaCs.EqualsIgnoreCase("true", GetProperty("qacover.optimize.rule.evaluation", "false"));
@@ -261,6 +264,11 @@ public virtual void SetStoreReportsLocation(string location)
 			storeReportsLocation = location;
 		}
 
+		public virtual string GetRuleServiceType()
+		{
+			return ruleServiceType;
+		}
+
 		public virtual string GetFpcServiceUrl()
 		{
 			return fpcServiceUrl;
@@ -271,6 +279,12 @@ public virtual string GetFpcServiceOptions()
 			return fpcServiceOptions;
 		}
 
+		public virtual Giis.Qacover.Core.Services.Configuration SetRuleServiceType(string ruleServiceType)
+		{
+			this.ruleServiceType = ruleServiceType;
+			return this;
+		}
+
 		public virtual Giis.Qacover.Core.Services.Configuration SetFpcServiceOptions(string fpcServiceOptions)
 		{
 			this.fpcServiceOptions = fpcServiceOptions;
diff --git a/net/QACover/Translated/Giis.Qacover.Core.Services/RuleServices.cs b/net/QACover/Translated/Giis.Qacover.Core.Services/RuleServices.cs
index 208b099..9fa6aae 100644
--- a/net/QACover/Translated/Giis.Qacover.Core.Services/RuleServices.cs
+++ b/net/QACover/Translated/Giis.Qacover.Core.Services/RuleServices.cs
@@ -54,7 +54,7 @@ private TdRulesApi GetApi()
 			return api;
 		}
 
-		public virtual QueryModel GetRulesModel(string sql, SchemaModel schema, string fpcOptions)
+		public virtual QueryModel GetFpcRulesModel(string sql, SchemaModel schema, string fpcOptions)
 		{
 			this.SetErrorContext("Generate SQLFpc coverage rules");
 			TdRules model = GetApi().GetRules(schema.GetModel(), sql, fpcOptions);
@@ -66,6 +66,18 @@ public virtual QueryModel GetRulesModel(string sql, SchemaModel schema, string f
 			return new QueryModel(model);
 		}
 
+		public virtual QueryModel GetMutationRulesModel(string sql, SchemaModel schema, string fpcOptions)
+		{
+			this.SetErrorContext("Generate SQLMutation coverage rules");
+			TdRules model = GetApi().GetMutants(schema.GetModel(), sql, fpcOptions);
+			InjectFaultIfNeeded(model);
+			if (!string.Empty.Equals(model.GetError()))
+			{
+				throw new QaCoverException(model.GetError());
+			}
+			return new QueryModel(model);
+		}
+
 		public virtual string GetRulesInput(string sql, SchemaModel schemaModel, string fpcOptions)
 		{
 			TdRulesBody body = new TdRulesBody();
diff --git a/net/QACover/Translated/Giis.Qacover.Core/CoverageManager.cs b/net/QACover/Translated/Giis.Qacover.Core/CoverageManager.cs
index 272747f..9ecaca2 100644
--- a/net/QACover/Translated/Giis.Qacover.Core/CoverageManager.cs
+++ b/net/QACover/Translated/Giis.Qacover.Core/CoverageManager.cs
@@ -126,6 +126,8 @@ public virtual void Run(RuleServices svc, StoreService store, QueryStatement stm
 			model.Reset();
 			result = new ResultVector(rules.Count);
 			stmt.SetVariant(new Variability(model.GetDbms()));
+			// Mutation requires a previous step to read query results
+			ruleDriver.PrepareEvaluation(stmt, stmt.GetSql());
 			// Executes and annotates the coverage/status of each rule
 			for (int i = 0; i < rules.Count; i++)
 			{
diff --git a/net/QACover/Translated/Giis.Qacover.Core/IQueryReader.cs b/net/QACover/Translated/Giis.Qacover.Core/IQueryReader.cs
new file mode 100644
index 0000000..754de38
--- /dev/null
+++ b/net/QACover/Translated/Giis.Qacover.Core/IQueryReader.cs
@@ -0,0 +1,24 @@
+/////////////////////////////////////////////////////////////////////////////////////////////
+/////// THIS FILE HAS BEEN AUTOMATICALLY CONVERTED FROM THE JAVA SOURCES. DO NOT EDIT ///////
+/////////////////////////////////////////////////////////////////////////////////////////////
+using System.Collections.Generic;
+
+
+namespace Giis.Qacover.Core
+{
+	/// <summary>Provides read access to the data stored in the database to evaluate the rules</summary>
+	public interface IQueryReader
+	{
+		/// <summary>
+		/// Determines if the execution of a query returns at least one row
+		/// (to evaluate the fpc coverage)
+		/// </summary>
+		bool HasRows();
+
+		/// <summary>Gets all rows returned by a sql statement</summary>
+		IList<string[]> GetRows();
+
+		/// <summary>Determines if the list of rows is the same than the returned by a sql statement</summary>
+		bool EqualRows(IList<string[]> expected);
+	}
+}
diff --git a/net/QACover/Translated/Giis.Qacover.Core/QueryStatement.cs b/net/QACover/Translated/Giis.Qacover.Core/QueryStatement.cs
index 58826dd..f8f71f3 100644
--- a/net/QACover/Translated/Giis.Qacover.Core/QueryStatement.cs
+++ b/net/QACover/Translated/Giis.Qacover.Core/QueryStatement.cs
@@ -6,7 +6,6 @@
 using Giis.Portable.Util;
 using Giis.Qacover.Core.Services;
 using Giis.Qacover.Model;
-using Giis.Qacover.Portable;
 using Java.Sql;
 using NLog;
 
@@ -140,36 +139,8 @@ private string ReplaceSingleParameter(string sourceSql, string name, string valu
 
 		public abstract Connection GetConnection();
 
-		/// <summary>
-		/// Determines if the execution of a query returns at least one row
-		/// (to evaluate the fpc coverage)
-		/// </summary>
-		public virtual bool HasRows(string sql)
-		{
-			string sqlWithValues = GetSqlWithValues(sql);
-			// any exception is propagated to detect failures in individual rules
-			Statement stmt = null;
-			ResultSet rs = null;
-			try
-			{
-				// do not use try with resources for java 1.6 compatibility
-				stmt = this.GetConnection().CreateStatement();
-				// NOSONAR
-				stmt.SetMaxRows(1);
-				rs = stmt.ExecuteQuery(sqlWithValues);
-				// NOSONAR
-				return rs.Next();
-			}
-			catch (SQLException e)
-			{
-				throw new QaCoverException("SpyStatementAdapter.hasRows", e);
-			}
-			finally
-			{
-				SafeClose(rs);
-				SafeClose(stmt);
-			}
-		}
+		/// <summary>Returns an object to browse the data accessed from the current connection</summary>
+		public abstract IQueryReader GetQueryReader(string sql);
 
 		/// <summary>
 		/// Determines if the query is a select, needed to filter other statements
@@ -187,36 +158,6 @@ public static bool IsSelectQuery(string sql, Logger log)
 			return false;
 		}
 
-		private void SafeClose(Statement stmt)
-		{
-			try
-			{
-				if (stmt != null)
-				{
-					stmt.Close();
-				}
-			}
-			catch (SQLException)
-			{
-			}
-		}
-
-		// no action
-		private void SafeClose(ResultSet rs)
-		{
-			try
-			{
-				if (rs != null)
-				{
-					rs.Close();
-				}
-			}
-			catch (SQLException)
-			{
-			}
-		}
-
-		// no action
 		public virtual Exception GetException()
 		{
 			return exception;
diff --git a/net/QACover/Translated/Giis.Qacover.Core/RuleDriver.cs b/net/QACover/Translated/Giis.Qacover.Core/RuleDriver.cs
index 62b5f87..fa4a915 100644
--- a/net/QACover/Translated/Giis.Qacover.Core/RuleDriver.cs
+++ b/net/QACover/Translated/Giis.Qacover.Core/RuleDriver.cs
@@ -23,6 +23,12 @@ public abstract class RuleDriver
 		/// <summary>Generate the model with the rules</summary>
 		public abstract QueryModel GetRules(RuleServices svc, string sql, SchemaModel schema, string fpcOptions);
 
+		/// <summary>
+		/// Executes the preliminary actions on the query before evaluating each rule
+		/// (only needed for mutation)
+		/// </summary>
+		public abstract void PrepareEvaluation(QueryStatement stmt, string sql);
+
 		/// <summary>Determines the coverage of a rule, saving the results and returning if it is covered</summary>
 		public virtual string EvaluateRule(RuleModel model, QueryStatement stmt)
 		{
diff --git a/net/QACover/Translated/Giis.Qacover.Core/RuleDriverFactory.cs b/net/QACover/Translated/Giis.Qacover.Core/RuleDriverFactory.cs
index 582910c..7968c8a 100644
--- a/net/QACover/Translated/Giis.Qacover.Core/RuleDriverFactory.cs
+++ b/net/QACover/Translated/Giis.Qacover.Core/RuleDriverFactory.cs
@@ -1,6 +1,7 @@
 /////////////////////////////////////////////////////////////////////////////////////////////
 /////// THIS FILE HAS BEEN AUTOMATICALLY CONVERTED FROM THE JAVA SOURCES. DO NOT EDIT ///////
 /////////////////////////////////////////////////////////////////////////////////////////////
+using Giis.Qacover.Core.Services;
 
 
 namespace Giis.Qacover.Core
@@ -17,7 +18,15 @@ public class RuleDriverFactory
 		/// </remarks>
 		public virtual RuleDriver GetDriver()
 		{
-			return new RuleDriverFpc();
+			if ("mutation".Equals(Configuration.GetInstance().GetRuleServiceType()))
+			{
+				return new RuleDriverMutation();
+			}
+			else
+			{
+				// fpc
+				return new RuleDriverFpc();
+			}
 		}
 	}
 }
diff --git a/net/QACover/Translated/Giis.Qacover.Core/RuleDriverFpc.cs b/net/QACover/Translated/Giis.Qacover.Core/RuleDriverFpc.cs
index f1fde33..897549d 100644
--- a/net/QACover/Translated/Giis.Qacover.Core/RuleDriverFpc.cs
+++ b/net/QACover/Translated/Giis.Qacover.Core/RuleDriverFpc.cs
@@ -15,12 +15,17 @@ public class RuleDriverFpc : RuleDriver
 	{
 		public override QueryModel GetRules(RuleServices svc, string sql, SchemaModel schema, string fpcOptions)
 		{
-			return svc.GetRulesModel(sql, schema, fpcOptions);
+			return svc.GetFpcRulesModel(sql, schema, fpcOptions);
 		}
 
+		public override void PrepareEvaluation(QueryStatement stmt, string sql)
+		{
+		}
+
+		// no preparation actions, evaluation is made by checking number of rows for each rule
 		protected internal override bool IsCovered(QueryStatement stmt, string sql)
 		{
-			return stmt.HasRows(sql);
+			return stmt.GetQueryReader(sql).HasRows();
 		}
 	}
 }
diff --git a/net/QACover/Translated/Giis.Qacover.Core/RuleDriverMutation.cs b/net/QACover/Translated/Giis.Qacover.Core/RuleDriverMutation.cs
new file mode 100644
index 0000000..0457385
--- /dev/null
+++ b/net/QACover/Translated/Giis.Qacover.Core/RuleDriverMutation.cs
@@ -0,0 +1,34 @@
+/////////////////////////////////////////////////////////////////////////////////////////////
+/////// THIS FILE HAS BEEN AUTOMATICALLY CONVERTED FROM THE JAVA SOURCES. DO NOT EDIT ///////
+/////////////////////////////////////////////////////////////////////////////////////////////
+using System.Collections.Generic;
+using Giis.Qacover.Core.Services;
+using Giis.Qacover.Model;
+
+
+namespace Giis.Qacover.Core
+{
+	/// <summary>
+	/// Delegate that performs the required actions
+	/// on the SQLMutation rules (get and evaluate the rules)
+	/// </summary>
+	public class RuleDriverMutation : RuleDriver
+	{
+		private IList<string[]> rows;
+
+		public override QueryModel GetRules(RuleServices svc, string sql, SchemaModel schema, string fpcOptions)
+		{
+			return svc.GetMutationRulesModel(sql, schema, fpcOptions);
+		}
+
+		public override void PrepareEvaluation(QueryStatement stmt, string sql)
+		{
+			this.rows = stmt.GetQueryReader(sql).GetRows();
+		}
+
+		protected internal override bool IsCovered(QueryStatement stmt, string sql)
+		{
+			return stmt.GetQueryReader(sql).EqualRows(this.rows);
+		}
+	}
+}
diff --git a/net/QACover/Translated/Giis.Qacover.Report/ClassHtmlWriter.cs b/net/QACover/Translated/Giis.Qacover.Report/ClassHtmlWriter.cs
index 3f2c9e0..27d987c 100644
--- a/net/QACover/Translated/Giis.Qacover.Report/ClassHtmlWriter.cs
+++ b/net/QACover/Translated/Giis.Qacover.Report/ClassHtmlWriter.cs
@@ -94,8 +94,8 @@ public virtual string GetRulesContent(string rulesContent)
 		public virtual string GetRuleContent(RuleModel rule)
 		{
 			string template = "    <tr class='rule-summary'>\n" + "        <td></td>\n" + "        <td class='coverage' rowspan='2'><strong>$ruleId$</strong> - dead:&nbsp;$ruleDead$ count:&nbsp;$ruleCount$</td>\n" + "        <td class='coverage' colspan='2'>\n" + "            category: $ruleCategory$ type: $ruleType$ subtype: $ruleSubtype$ location: $ruleLocation$\n"
-				 + "            <div class='params'>(run params not available)</div>\n" + "        </td>\n" + "    </tr>\n" + "    <tr class='rule-sql'>\n" + "        <td></td>\n" + "            <td class='$ruleStatus$'>$ruleDescription$</td>\n" + "            <td class='$ruleStatus$'>$ruleSql$</td>\n"
-				 + "    </tr>\n" + "    $ruleErrors$";
+				 + "            <div class='params'>(run params not available)</div>\n" + "        </td>\n" + "    </tr>\n" + "    <tr class='rule-sql'>\n" + "        <td></td>\n" + (string.Empty.Equals(rule.GetDescription()) ? "            <td class='$ruleStatus$ rowspan='2'>$ruleSql$</td>\n" : 
+				"            <td class='$ruleStatus$'>$ruleDescription$</td>\n" + "            <td class='$ruleStatus$'>$ruleSql$</td>\n") + "    </tr>\n" + "    $ruleErrors$";
 			// needs a complete row to allow error message span across description and sql columns
 			return template.Replace("$ruleId$", rule.GetId()).Replace("$ruleDead$", rule.GetDead().ToString()).Replace("$ruleCount$", rule.GetCount().ToString()).Replace("$ruleCategory$", rule.GetCategory()).Replace("$ruleType$", rule.GetMainType()).Replace("$ruleSubtype$", rule.GetSubtype())
 				.Replace("$ruleLocation$", Encode(rule.GetLocation())).Replace("$ruleStatus$", rule.GetDead() > 0 ? "covered" : "uncovered").Replace("$ruleDescription$", GetDescriptionHtml(Encode(rule.GetDescription()))).Replace("$ruleSql$", GetSqlHtml(Encode(rule.GetSql()))).Replace("$ruleErrors$"
diff --git a/net/QACoverTest/Translated/Test4giis.Qacover/TestFaults.cs b/net/QACoverTest/Translated/Test4giis.Qacover/TestFaults.cs
index 8e51407..3855a21 100644
--- a/net/QACoverTest/Translated/Test4giis.Qacover/TestFaults.cs
+++ b/net/QACoverTest/Translated/Test4giis.Qacover/TestFaults.cs
@@ -191,8 +191,8 @@ public virtual void TestFaultServiceRunRules()
 			IList<RuleModel> rules = model.GetRules();
 			//NOSONAR no using typed names for compatibility with downgrade to jdk 1.4
 			string errorString = rules[0].GetErrorString();
-			AssertExceptionMessage(variant.IsJava() ? (variant.IsJava8() ? "giis.qacover.portable.QaCoverException: SpyStatementAdapter.hasRows. Caused by: org.sqlite.SQLiteException: [SQLITE_ERROR] SQL error or missing database (near \"selectar\": syntax error)" : "giis.qacover.portable.QaCoverException: SpyStatementAdapter.hasRows. Caused by: org.h2.jdbc.JdbcSQLException: Syntax error in SQL statement"
-				) : "Giis.Qacover.Portable.QaCoverException: SpyStatementAdapter.hasRows. Caused by: System.Data.SQLite.SQLiteException: SQL logic error\nnear \"selectar\": syntax error", errorString);
+			AssertExceptionMessage(variant.IsJava() ? (variant.IsJava8() ? "giis.qacover.portable.QaCoverException: QueryReader.hasRows. Caused by: org.sqlite.SQLiteException: [SQLITE_ERROR] SQL error or missing database (near \"selectar\": syntax error)" : "giis.qacover.portable.QaCoverException: QueryReader.hasRows. Caused by: org.h2.jdbc.JdbcSQLException: Syntax error in SQL statement"
+				) : "Giis.Qacover.Portable.QaCoverException: QueryReader.hasRows. Caused by: System.Data.SQLite.SQLiteException: SQL logic error\nnear \"selectar\": syntax error", errorString);
 		}
 
 		//: "giis.Qacover.Portable.QaCoverException: SpyStatementAdapter.hasRows. Caused by: Microsoft.Data.Sqlite.SqliteException: SQLite Error 1: 'near \"selectar\": syntax error'."
@@ -220,8 +220,8 @@ public virtual void TestMultipleFaultsQuery()
 			AssertMultipleFaults(true, "qerror=1,count=0,dead=0", "Error at : giis.qacover.portable.QaCoverException: Injected unexpected exception");
 		}
 
-		internal string exceptionInvalidSql = new Variability().IsJava() ? (new Variability().IsJava8() ? "giis.qacover.portable.QaCoverException: SpyStatementAdapter.hasRows. Caused by: org.sqlite.SQLiteException: [SQLITE_ERROR] SQL error or missing database (near \"selectar\": syntax error)"
-			 : "giis.qacover.portable.QaCoverException: SpyStatementAdapter.hasRows. Caused by: org.h2.jdbc.JdbcSQLException: Syntax error in SQL statement") : "Giis.Qacover.Portable.QaCoverException: SpyStatementAdapter.hasRows. Caused by: System.Data.SQLite.SQLiteException: SQL logic error\nnear \"selectar\": syntax error";
+		internal string exceptionInvalidSql = new Variability().IsJava() ? (new Variability().IsJava8() ? "giis.qacover.portable.QaCoverException: QueryReader.hasRows. Caused by: org.sqlite.SQLiteException: [SQLITE_ERROR] SQL error or missing database (near \"selectar\": syntax error)" : 
+			"giis.qacover.portable.QaCoverException: QueryReader.hasRows. Caused by: org.h2.jdbc.JdbcSQLException: Syntax error in SQL statement") : "Giis.Qacover.Portable.QaCoverException: QueryReader.hasRows. Caused by: System.Data.SQLite.SQLiteException: SQL logic error\nnear \"selectar\": syntax error";
 
 		//: "giis.Qacover.Portable.QaCoverException: SpyStatementAdapter.hasRows. Caused by: Microsoft.Data.Sqlite.SqliteException: SQLite Error 1: 'near \"selectar\": syntax error'."
 		/// <exception cref="Java.Sql.SQLException"/>
diff --git a/net/build.xml b/net/build.xml
index 5a121b9..b99fbea 100644
--- a/net/build.xml
+++ b/net/build.xml
@@ -41,6 +41,7 @@
         </fileset>
         <fileset dir="../qacover-core/src/test/java" >
           <exclude name="**/test4giis/qacoversample/*.java" />
+          <exclude name="**/test4giis/qacover/TestMutationEvaluation.java" />
         </fileset>
       </copy>
       <!-- As of VisualAssert 2.4.1 the use of generics in the hierarchy of SoftVisualAssert
diff --git a/net/resources/qacover-report/all-data-by-run-order.txt b/net/resources/qacover-report/all-data-by-run-order.txt
index 0010979..32942c8 100644
--- a/net/resources/qacover-report/all-data-by-run-order.txt
+++ b/net/resources/qacover-report/all-data-by-run-order.txt
@@ -457,7 +457,7 @@ rule0: <fpcrule count="1" error="1"><id>1</id><category>S</category><type>B</typ
     <description>--Some row in the table such that:
 --The WHERE condition fulfills:
   --(B+) num = 12</description>
-    <error>Giis.Qacover.Portable.QaCoverException: SpyStatementAdapter.hasRows. Caused by: System.Data.SQLite.SQLiteException: SQL logic error
+    <error>Giis.Qacover.Portable.QaCoverException: QueryReader.hasRows. Caused by: System.Data.SQLite.SQLiteException: SQL logic error
 near "selectar": syntax error</error>
   </fpcrule>
 rule1: <fpcrule count="1" dead="0"><id>2</id><category>S</category><type>B</type><subtype>B=F</subtype><location>1.w.1.[WHERE num &lt; 11]</location>
@@ -487,9 +487,9 @@ rule0: <fpcrule count="3" error="3"><id>1</id><category>S</category><type>B</typ
     <description>--Some row in the table such that:
 --The WHERE condition fulfills:
   --(B+) num = 10</description>
-    <error>Giis.Qacover.Portable.QaCoverException: SpyStatementAdapter.hasRows. Caused by: System.Data.SQLite.SQLiteException: SQL logic error
+    <error>Giis.Qacover.Portable.QaCoverException: QueryReader.hasRows. Caused by: System.Data.SQLite.SQLiteException: SQL logic error
 near "selectar": syntax error
-Giis.Qacover.Portable.QaCoverException: SpyStatementAdapter.hasRows. Caused by: System.Data.SQLite.SQLiteException: SQL logic error
+Giis.Qacover.Portable.QaCoverException: QueryReader.hasRows. Caused by: System.Data.SQLite.SQLiteException: SQL logic error
 no such table: notable</error>
   </fpcrule>
 rule1: <fpcrule count="3" dead="0"><id>2</id><category>S</category><type>B</type><subtype>B=F</subtype><location>1.w.1.[WHERE num &lt; 9]</location>
@@ -519,9 +519,9 @@ rule0: <fpcrule count="3" error="3"><id>1</id><category>S</category><type>B</typ
     <description>--Some row in the table such that:
 --The WHERE condition fulfills:
   --(B+) num = 10</description>
-    <error>Giis.Qacover.Portable.QaCoverException: SpyStatementAdapter.hasRows. Caused by: System.Data.SQLite.SQLiteException: SQL logic error
+    <error>Giis.Qacover.Portable.QaCoverException: QueryReader.hasRows. Caused by: System.Data.SQLite.SQLiteException: SQL logic error
 near "selectar": syntax error
-Giis.Qacover.Portable.QaCoverException: SpyStatementAdapter.hasRows. Caused by: System.Data.SQLite.SQLiteException: SQL logic error
+Giis.Qacover.Portable.QaCoverException: QueryReader.hasRows. Caused by: System.Data.SQLite.SQLiteException: SQL logic error
 no such table: notable</error>
   </fpcrule>
 rule1: <fpcrule count="3" dead="0"><id>2</id><category>S</category><type>B</type><subtype>B=F</subtype><location>1.w.1.[WHERE num &lt; 9]</location>
@@ -551,9 +551,9 @@ rule0: <fpcrule count="3" error="3"><id>1</id><category>S</category><type>B</typ
     <description>--Some row in the table such that:
 --The WHERE condition fulfills:
   --(B+) num = 10</description>
-    <error>Giis.Qacover.Portable.QaCoverException: SpyStatementAdapter.hasRows. Caused by: System.Data.SQLite.SQLiteException: SQL logic error
+    <error>Giis.Qacover.Portable.QaCoverException: QueryReader.hasRows. Caused by: System.Data.SQLite.SQLiteException: SQL logic error
 near "selectar": syntax error
-Giis.Qacover.Portable.QaCoverException: SpyStatementAdapter.hasRows. Caused by: System.Data.SQLite.SQLiteException: SQL logic error
+Giis.Qacover.Portable.QaCoverException: QueryReader.hasRows. Caused by: System.Data.SQLite.SQLiteException: SQL logic error
 no such table: notable</error>
   </fpcrule>
 rule1: <fpcrule count="3" dead="0"><id>2</id><category>S</category><type>B</type><subtype>B=F</subtype><location>1.w.1.[WHERE num &lt; 9]</location>
diff --git a/net/resources/qacover-report/index.html b/net/resources/qacover-report/index.html
index a0f9044..16f12d3 100644
--- a/net/resources/qacover-report/index.html
+++ b/net/resources/qacover-report/index.html
@@ -55,7 +55,7 @@ <h2>SQL Query FPC Coverage</h2>
   </table>
 
 <div><span style="float:right;"><small>
-Generated by: QACover netcore - [version 1.6.4-SNAPSHOT+3f59c7f96bfdbb0c0f17f218e366829414b6e562] - <a href="https://github.com/giis-uniovi/qacover/issues/new">[Submit a problem report]</a>
+Generated by: QACover netcore - [version 1.6.4-SNAPSHOT+d41934206d4106ab6e670f05928c8d4470c266dd] - <a href="https://github.com/giis-uniovi/qacover/issues/new">[Submit a problem report]</a>
 </small></span></div>
 </div>
 </body>
diff --git a/net/resources/qacover-report/test4giis.qacoverapp.AppSimpleJdbc.html b/net/resources/qacover-report/test4giis.qacoverapp.AppSimpleJdbc.html
index b0471a5..35614b4 100644
--- a/net/resources/qacover-report/test4giis.qacoverapp.AppSimpleJdbc.html
+++ b/net/resources/qacover-report/test4giis.qacoverapp.AppSimpleJdbc.html
@@ -554,7 +554,7 @@ <h4><a href='./index.html'>[Index]</a> Test4giis.Qacoverapp.AppSimpleJdbc</h4>
 </div>
 
 <div><span style="float:right;"><small>
-Generated by: QACover netcore - [version 1.6.4-SNAPSHOT+3f59c7f96bfdbb0c0f17f218e366829414b6e562] - <a href="https://github.com/giis-uniovi/qacover/issues/new">[Submit a problem report]</a>
+Generated by: QACover netcore - [version 1.6.4-SNAPSHOT+d41934206d4106ab6e670f05928c8d4470c266dd] - <a href="https://github.com/giis-uniovi/qacover/issues/new">[Submit a problem report]</a>
 </small></span></div>
 </div>
 </body>
diff --git a/net/resources/qacover-report/test4giis.qacoverapp.AppSimpleJdbc2.html b/net/resources/qacover-report/test4giis.qacoverapp.AppSimpleJdbc2.html
index b30b89b..ca3123e 100644
--- a/net/resources/qacover-report/test4giis.qacoverapp.AppSimpleJdbc2.html
+++ b/net/resources/qacover-report/test4giis.qacoverapp.AppSimpleJdbc2.html
@@ -231,7 +231,7 @@ <h4><a href='./index.html'>[Index]</a> Test4giis.Qacoverapp.AppSimpleJdbc2</h4>
 </div>
 
 <div><span style="float:right;"><small>
-Generated by: QACover netcore - [version 1.6.4-SNAPSHOT+3f59c7f96bfdbb0c0f17f218e366829414b6e562] - <a href="https://github.com/giis-uniovi/qacover/issues/new">[Submit a problem report]</a>
+Generated by: QACover netcore - [version 1.6.4-SNAPSHOT+d41934206d4106ab6e670f05928c8d4470c266dd] - <a href="https://github.com/giis-uniovi/qacover/issues/new">[Submit a problem report]</a>
 </small></span></div>
 </div>
 </body>
diff --git a/net/resources/qacover-report/test4giis.qacoverapp.AppSimpleJdbc3Errors.html b/net/resources/qacover-report/test4giis.qacoverapp.AppSimpleJdbc3Errors.html
index 7a53f14..e28773b 100644
--- a/net/resources/qacover-report/test4giis.qacoverapp.AppSimpleJdbc3Errors.html
+++ b/net/resources/qacover-report/test4giis.qacoverapp.AppSimpleJdbc3Errors.html
@@ -215,7 +215,7 @@ <h4><a href='./index.html'>[Index]</a> Test4giis.Qacoverapp.AppSimpleJdbc3Errors
             <td class='uncovered'>--Some row in the table such that: <br class='canhide'/>--The WHERE condition fulfills: <br class='canhide'/>  --(B+) num = 12</td>
             <td class='uncovered'>selectar id,num,text from test where num &lt; 9</td>
     </tr>
-    <tr class='rule-error'><td colspan='2'></td><td colspan='2'><span style="color:red;">Rule error: Giis.Qacover.Portable.QaCoverException: SpyStatementAdapter.hasRows. Caused by: System.Data.SQLite.SQLiteException: SQL logic error
+    <tr class='rule-error'><td colspan='2'></td><td colspan='2'><span style="color:red;">Rule error: Giis.Qacover.Portable.QaCoverException: QueryReader.hasRows. Caused by: System.Data.SQLite.SQLiteException: SQL logic error
 <br/>near "selectar": syntax error</span></td></tr>
     <tr class='rule-summary'>
         <td></td>
@@ -288,9 +288,9 @@ <h4><a href='./index.html'>[Index]</a> Test4giis.Qacoverapp.AppSimpleJdbc3Errors
             <td class='uncovered'>--Some row in the table such that: <br class='canhide'/>--The WHERE condition fulfills: <br class='canhide'/>  --(B+) num = 10</td>
             <td class='uncovered'>select id,num,text from notable where num &lt; 9</td>
     </tr>
-    <tr class='rule-error'><td colspan='2'></td><td colspan='2'><span style="color:red;">Rule error: Giis.Qacover.Portable.QaCoverException: SpyStatementAdapter.hasRows. Caused by: System.Data.SQLite.SQLiteException: SQL logic error
+    <tr class='rule-error'><td colspan='2'></td><td colspan='2'><span style="color:red;">Rule error: Giis.Qacover.Portable.QaCoverException: QueryReader.hasRows. Caused by: System.Data.SQLite.SQLiteException: SQL logic error
 <br/>near "selectar": syntax error
-<br/>Giis.Qacover.Portable.QaCoverException: SpyStatementAdapter.hasRows. Caused by: System.Data.SQLite.SQLiteException: SQL logic error
+<br/>Giis.Qacover.Portable.QaCoverException: QueryReader.hasRows. Caused by: System.Data.SQLite.SQLiteException: SQL logic error
 <br/>no such table: notable</span></td></tr>
     <tr class='rule-summary'>
         <td></td>
@@ -329,7 +329,7 @@ <h4><a href='./index.html'>[Index]</a> Test4giis.Qacoverapp.AppSimpleJdbc3Errors
 </div>
 
 <div><span style="float:right;"><small>
-Generated by: QACover netcore - [version 1.6.4-SNAPSHOT+3f59c7f96bfdbb0c0f17f218e366829414b6e562] - <a href="https://github.com/giis-uniovi/qacover/issues/new">[Submit a problem report]</a>
+Generated by: QACover netcore - [version 1.6.4-SNAPSHOT+d41934206d4106ab6e670f05928c8d4470c266dd] - <a href="https://github.com/giis-uniovi/qacover/issues/new">[Submit a problem report]</a>
 </small></span></div>
 </div>
 </body>
diff --git a/qacover-core/src/main/java/giis/qacover/core/CoverageManager.java b/qacover-core/src/main/java/giis/qacover/core/CoverageManager.java
index 8dddc6a..80c76c0 100644
--- a/qacover-core/src/main/java/giis/qacover/core/CoverageManager.java
+++ b/qacover-core/src/main/java/giis/qacover/core/CoverageManager.java
@@ -102,7 +102,7 @@ public void run(RuleServices svc, StoreService store, QueryStatement stmt, Confi
 		svc.setErrorContext("Run SQLFpc coverage rules");
 		store.setLastSqlRun(stmt.getSql());
 		StringBuilder logsb = new StringBuilder();
-
+		
 		List<RuleModel> rules = model.getRules();
 		FaultInjector injector = stmt.getFaultInjector();
 		if (injector != null && injector.isSingleRuleFaulty())
@@ -110,6 +110,10 @@ public void run(RuleServices svc, StoreService store, QueryStatement stmt, Confi
 		model.reset();
 		result = new ResultVector(rules.size());
 		stmt.setVariant(new Variability(model.getDbms()));
+		
+		// Mutation requires a previous step to read query results
+		ruleDriver.prepareEvaluation(stmt, stmt.getSql());
+
 		// Executes and annotates the coverage/status of each rule
 		for (int i = 0; i < rules.size(); i++) {
 			RuleModel ruleModel = rules.get(i);
diff --git a/qacover-core/src/main/java/giis/qacover/core/IQueryReader.java b/qacover-core/src/main/java/giis/qacover/core/IQueryReader.java
new file mode 100644
index 0000000..9f6a4e4
--- /dev/null
+++ b/qacover-core/src/main/java/giis/qacover/core/IQueryReader.java
@@ -0,0 +1,26 @@
+package giis.qacover.core;
+
+import java.util.List;
+
+/**
+ * Provides read access to the data stored in the database to evaluate the rules
+ */
+public interface IQueryReader {
+	
+	/**
+	 * Determines if the execution of a query returns at least one row
+	 * (to evaluate the fpc coverage)
+	 */
+	public boolean hasRows();
+
+	/**
+	 * Gets all rows returned by a sql statement
+	 */
+	public List<String[]> getRows();
+	
+	/**
+	 * Determines if the list of rows is the same than the returned by a sql statement
+	 */
+	public boolean equalRows(List<String[]> expected);
+
+}
diff --git a/qacover-core/src/main/java/giis/qacover/core/QueryStatement.java b/qacover-core/src/main/java/giis/qacover/core/QueryStatement.java
index 73de525..758c0c2 100644
--- a/qacover-core/src/main/java/giis/qacover/core/QueryStatement.java
+++ b/qacover-core/src/main/java/giis/qacover/core/QueryStatement.java
@@ -1,9 +1,6 @@
 package giis.qacover.core;
 
 import java.sql.Connection;
-import java.sql.ResultSet;
-import java.sql.SQLException;
-import java.sql.Statement;
 import java.util.ArrayList;
 import java.util.List;
 
@@ -15,7 +12,6 @@
 import giis.qacover.model.QueryParameters;
 import giis.qacover.model.QueryWithParameters;
 import giis.qacover.model.Variability;
-import giis.qacover.portable.QaCoverException;
 
 /**
  * Representation of a jdbc Statement that has been intercepted by p6spy.
@@ -111,27 +107,10 @@ private String replaceSingleParameter(String sourceSql, String name, String valu
 	public abstract Connection getConnection();
 
 	/**
-	 * Determines if the execution of a query returns at least one row
-	 * (to evaluate the fpc coverage)
+	 * Returns an object to browse the data accessed from the current connection
 	 */
-	public boolean hasRows(String sql) {
-		String sqlWithValues = getSqlWithValues(sql);
-		// any exception is propagated to detect failures in individual rules
-		Statement stmt = null;
-		ResultSet rs = null;
-		try { // do not use try with resources for java 1.6 compatibility
-			stmt = this.getConnection().createStatement(); // NOSONAR
-			stmt.setMaxRows(1);
-			rs = stmt.executeQuery(sqlWithValues); // NOSONAR
-			return rs.next();
-		} catch (SQLException e) {
-			throw new QaCoverException("SpyStatementAdapter.hasRows", e);
-		} finally {
-			safeClose(rs);
-			safeClose(stmt);
-		}
-	}
-
+	public abstract IQueryReader getQueryReader(String sql);
+	
 	/**
 	 * Determines if the query is a select, needed to filter other statements
 	 * when a generic jdbc execute() method is used (does not differentiates
@@ -145,22 +124,6 @@ public static boolean isSelectQuery(String sql, Logger log) {
 		return false;
 	}
 
-	private void safeClose(Statement stmt) {
-		try {
-			if (stmt != null)
-				stmt.close();
-		} catch (SQLException e) {
-			// no action
-		}
-	}
-	private void safeClose(ResultSet rs) {
-		try {
-			if (rs != null)
-				rs.close();
-		} catch (SQLException e) {
-			// no action
-		}
-	}
 	public Exception getException() {
 		return exception;
 	}
diff --git a/qacover-core/src/main/java/giis/qacover/core/RuleDriver.java b/qacover-core/src/main/java/giis/qacover/core/RuleDriver.java
index f9b24c4..c920282 100644
--- a/qacover-core/src/main/java/giis/qacover/core/RuleDriver.java
+++ b/qacover-core/src/main/java/giis/qacover/core/RuleDriver.java
@@ -19,6 +19,12 @@ public abstract class RuleDriver {
 	 */
 	public abstract QueryModel getRules(RuleServices svc, String sql, SchemaModel schema, String fpcOptions);
 
+	/**
+	 * Executes the preliminary actions on the query before evaluating each rule
+	 * (only needed for mutation)
+	 */
+	public abstract void prepareEvaluation(QueryStatement stmt, String sql);
+	
 	/**
 	 * Determines the coverage of a rule, saving the results and returning if it is covered
 	 */
diff --git a/qacover-core/src/main/java/giis/qacover/core/RuleDriverFactory.java b/qacover-core/src/main/java/giis/qacover/core/RuleDriverFactory.java
index 7bdff51..fa1354b 100644
--- a/qacover-core/src/main/java/giis/qacover/core/RuleDriverFactory.java
+++ b/qacover-core/src/main/java/giis/qacover/core/RuleDriverFactory.java
@@ -1,5 +1,7 @@
 package giis.qacover.core;
 
+import giis.qacover.core.services.Configuration;
+
 public class RuleDriverFactory {
 
 	/**
@@ -7,6 +9,9 @@ public class RuleDriverFactory {
 	 * options. At this moment, only fpc
 	 */
 	public RuleDriver getDriver() {
-		return new RuleDriverFpc();
+		if ("mutation".equals(Configuration.getInstance().getRuleServiceType()))
+			return new RuleDriverMutation();
+		else // fpc
+			return new RuleDriverFpc();
 	}
 }
diff --git a/qacover-core/src/main/java/giis/qacover/core/RuleDriverFpc.java b/qacover-core/src/main/java/giis/qacover/core/RuleDriverFpc.java
index 5344734..0dfd7e4 100644
--- a/qacover-core/src/main/java/giis/qacover/core/RuleDriverFpc.java
+++ b/qacover-core/src/main/java/giis/qacover/core/RuleDriverFpc.java
@@ -12,12 +12,17 @@ public class RuleDriverFpc extends RuleDriver {
 
 	@Override
 	public QueryModel getRules(RuleServices svc, String sql, SchemaModel schema, String fpcOptions) {
-		return svc.getRulesModel(sql, schema, fpcOptions);
+		return svc.getFpcRulesModel(sql, schema, fpcOptions);
 	}
 
+	@Override
+	public void prepareEvaluation(QueryStatement stmt, String sql) {
+		// no preparation actions, evaluation is made by checking number of rows for each rule
+	}
+	
 	@Override
 	protected boolean isCovered(QueryStatement stmt, String sql) {
-		return stmt.hasRows(sql);
+		return stmt.getQueryReader(sql).hasRows();
 	}
 	
 }
diff --git a/qacover-core/src/main/java/giis/qacover/core/RuleDriverMutation.java b/qacover-core/src/main/java/giis/qacover/core/RuleDriverMutation.java
new file mode 100644
index 0000000..270af5a
--- /dev/null
+++ b/qacover-core/src/main/java/giis/qacover/core/RuleDriverMutation.java
@@ -0,0 +1,32 @@
+package giis.qacover.core;
+
+import java.util.List;
+
+import giis.qacover.core.services.RuleServices;
+import giis.qacover.model.QueryModel;
+import giis.qacover.model.SchemaModel;
+
+/**
+ * Delegate that performs the required actions
+ * on the SQLMutation rules (get and evaluate the rules)
+ */
+public class RuleDriverMutation extends RuleDriver {
+
+	private List<String[]> rows;
+	
+	@Override
+	public QueryModel getRules(RuleServices svc, String sql, SchemaModel schema, String fpcOptions) {
+		return svc.getMutationRulesModel(sql, schema, fpcOptions);
+	}
+
+	@Override
+	public void prepareEvaluation(QueryStatement stmt, String sql) {
+		this.rows = stmt.getQueryReader(sql).getRows();
+	}
+	
+	@Override
+	protected boolean isCovered(QueryStatement stmt, String sql) {
+		return stmt.getQueryReader(sql).equalRows(this.rows);
+	}
+
+}
diff --git a/qacover-core/src/main/java/giis/qacover/core/services/Configuration.java b/qacover-core/src/main/java/giis/qacover/core/services/Configuration.java
index a15e46c..d45097d 100644
--- a/qacover-core/src/main/java/giis/qacover/core/services/Configuration.java
+++ b/qacover-core/src/main/java/giis/qacover/core/services/Configuration.java
@@ -28,6 +28,7 @@ public class Configuration { // NOSONAR singleton allowed
 	private String storeRulesLocation;
 	private String cacheRulesLocation;
 	private String storeReportsLocation;
+	private String ruleServiceType;
 	private String fpcServiceUrl;
 	private String fpcServiceOptions;
 	private boolean optimizeRuleEvaluation;
@@ -55,6 +56,7 @@ public Configuration reset() {
 		String defaultReportsSubDir = FileUtil.getPath(Parameters.getReportSubdir(), QACOVER_NAME, "reports");
 		storeRulesLocation = FileUtil.getPath(storeRootLocation, getProperty("qacover.store.rules", defaultRulesSubDir));
 		storeReportsLocation = FileUtil.getPath(storeRootLocation, getProperty("qacover.store.reports", defaultReportsSubDir));
+		ruleServiceType = "fpc";
 		fpcServiceUrl = getProperty("qacover.fpc.url", "https://in2test.lsi.uniovi.es/tdrules/api/v4");
 		fpcServiceOptions = getProperty("qacover.fpc.options", "");
 		optimizeRuleEvaluation = JavaCs.equalsIgnoreCase("true", getProperty("qacover.optimize.rule.evaluation", "false"));
@@ -202,12 +204,19 @@ public void setStoreReportsLocation(String location) {
 		storeReportsLocation = location;
 	}
 
+	public String getRuleServiceType() {
+		return ruleServiceType;
+	}
 	public String getFpcServiceUrl() {
 		return fpcServiceUrl;
 	}
 	public String getFpcServiceOptions() {
 		return fpcServiceOptions;
 	}
+	public Configuration setRuleServiceType(String ruleServiceType) {
+		this.ruleServiceType = ruleServiceType;
+		return this;
+	}
 	public Configuration setFpcServiceOptions(String fpcServiceOptions) {
 		this.fpcServiceOptions = fpcServiceOptions;
 		return this;
diff --git a/qacover-core/src/main/java/giis/qacover/core/services/RuleServices.java b/qacover-core/src/main/java/giis/qacover/core/services/RuleServices.java
index 1ef8a75..bba4efe 100644
--- a/qacover-core/src/main/java/giis/qacover/core/services/RuleServices.java
+++ b/qacover-core/src/main/java/giis/qacover/core/services/RuleServices.java
@@ -51,7 +51,7 @@ private TdRulesApi getApi() {
 		return api;
 	}
 
-	public QueryModel getRulesModel(String sql, SchemaModel schema, String fpcOptions) {
+	public QueryModel getFpcRulesModel(String sql, SchemaModel schema, String fpcOptions) {
 		this.setErrorContext("Generate SQLFpc coverage rules");
 		TdRules model = getApi().getRules(schema.getModel(), sql, fpcOptions);
 		injectFaultIfNeeded(model);
@@ -60,6 +60,15 @@ public QueryModel getRulesModel(String sql, SchemaModel schema, String fpcOption
 		return new QueryModel(model);
 	}
 
+	public QueryModel getMutationRulesModel(String sql, SchemaModel schema, String fpcOptions) {
+		this.setErrorContext("Generate SQLMutation coverage rules");
+		TdRules model = getApi().getMutants(schema.getModel(), sql, fpcOptions);
+		injectFaultIfNeeded(model);
+		if (!"".equals(model.getError()))
+			throw new QaCoverException(model.getError());
+		return new QueryModel(model);
+	}
+
 	public String getRulesInput(String sql, SchemaModel schemaModel, String fpcOptions) {
 		TdRulesBody body = new TdRulesBody();
 		body.setQuery(sql);
diff --git a/qacover-core/src/main/java/giis/qacover/driver/QueryReader.java b/qacover-core/src/main/java/giis/qacover/driver/QueryReader.java
new file mode 100644
index 0000000..6a495d5
--- /dev/null
+++ b/qacover-core/src/main/java/giis/qacover/driver/QueryReader.java
@@ -0,0 +1,91 @@
+package giis.qacover.driver;
+
+import java.sql.Connection;
+import java.sql.ResultSet;
+import java.sql.SQLException;
+import java.sql.Statement;
+import java.util.ArrayList;
+import java.util.List;
+
+import giis.qacover.core.IQueryReader;
+import giis.qacover.portable.QaCoverException;
+
+/**
+ * Provides access to the data stored in the database to evaluate the rules
+ */
+public class QueryReader implements IQueryReader {
+	private Connection conn;
+	private String sql;
+	
+	public QueryReader(Connection conn, String sql) {
+		this.conn = conn;
+		this.sql = sql;
+	}
+
+	@Override
+	public boolean hasRows() {
+		// any exception is propagated to detect failures in individual rules
+		try  (Statement stmt = conn.createStatement()) {
+			stmt.setMaxRows(1);
+			try (ResultSet rs = stmt.executeQuery(sql)) {
+				return rs.next();
+			}
+		} catch (SQLException e) {
+			throw new QaCoverException("QueryReader.hasRows", e);
+		}
+	}
+
+	@Override
+	public List<String[]> getRows() {
+		List<String[]> rows = new ArrayList<>();
+		try (Statement stmt = conn.createStatement(); 
+				ResultSet rs = stmt.executeQuery(sql)) {
+			int numCols = rs.getMetaData().getColumnCount();
+			while (rs.next())
+				rows.add(getRow(rs, numCols));
+			return rows;
+		} catch (SQLException e) {
+			throw new QaCoverException("QueryReader.getRows", e);
+		}
+	}
+
+	private String[] getRow(ResultSet rs, int numCols) throws SQLException {
+		String[] row = new String[numCols];
+		for (int i = 0; i < numCols; i++) {
+			String value = rs.getString(i + 1);
+			row[i] = rs.wasNull() ? null : value;
+		}
+		return row;
+	}
+	
+	@Override
+	public boolean equalRows(List<String[]> expected) {
+		int currentRow =-1;
+		try (Statement stmt = conn.createStatement(); ResultSet rs = stmt.executeQuery(sql)) {
+			int numCols = rs.getMetaData().getColumnCount();
+			while (rs.next()) {
+				currentRow++;
+				if (currentRow>expected.size() -1) // more rows in db than in the list
+					return false;
+				if (!equalRow(rs, expected.get(currentRow), numCols))
+					return false;
+			}
+			if (expected.size()>currentRow+1)
+				return false;
+			return true;
+		} catch (SQLException e) {
+			throw new QaCoverException("QueryReader.equalRows", e);
+		}
+	}
+	private boolean equalRow(ResultSet rs, String[] expected, int numCols) throws SQLException {
+		if (expected.length!=numCols)
+			return false;
+		String[] actual=getRow(rs,numCols);
+		for (int i=0; i<expected.length; i++)
+			if (expected[i]==null && actual[i]!=null || expected[i]!=null && actual[i]==null
+			|| (expected[i]!=null && actual[i]!=null && !expected[i].equals(actual[i])))
+			return false;
+		return true;
+	}
+
+}
diff --git a/qacover-core/src/main/java/giis/qacover/driver/StatementAdapter.java b/qacover-core/src/main/java/giis/qacover/driver/StatementAdapter.java
index d9efff8..39c9bae 100644
--- a/qacover-core/src/main/java/giis/qacover/driver/StatementAdapter.java
+++ b/qacover-core/src/main/java/giis/qacover/driver/StatementAdapter.java
@@ -117,4 +117,9 @@ public Connection getConnection() {
 		return p6stmt.getConnectionInformation().getConnection();
 	}
 	
+	@Override
+	public IQueryReader getQueryReader(String sql) {
+		return new QueryReader(this.getConnection(), getSqlWithValues(sql));
+	}
+
 }
diff --git a/qacover-core/src/test/java/test4giis/qacover/TestFaults.java b/qacover-core/src/test/java/test4giis/qacover/TestFaults.java
index 89a5620..0853ac0 100644
--- a/qacover-core/src/test/java/test4giis/qacover/TestFaults.java
+++ b/qacover-core/src/test/java/test4giis/qacover/TestFaults.java
@@ -175,9 +175,9 @@ public void testFaultServiceRunRules() throws SQLException {
 		List<RuleModel> rules=model.getRules(); //NOSONAR no using typed names for compatibility with downgrade to jdk 1.4
 		String errorString=rules.get(0).getErrorString();
 		assertExceptionMessage(variant.isJava()
-				? (variant.isJava8() ? "giis.qacover.portable.QaCoverException: SpyStatementAdapter.hasRows. Caused by: org.sqlite.SQLiteException: [SQLITE_ERROR] SQL error or missing database (near \"selectar\": syntax error)"
-						   : "giis.qacover.portable.QaCoverException: SpyStatementAdapter.hasRows. Caused by: org.h2.jdbc.JdbcSQLException: Syntax error in SQL statement")
-				: "Giis.Qacover.Portable.QaCoverException: SpyStatementAdapter.hasRows. Caused by: System.Data.SQLite.SQLiteException: SQL logic error\nnear \"selectar\": syntax error"
+				? (variant.isJava8() ? "giis.qacover.portable.QaCoverException: QueryReader.hasRows. Caused by: org.sqlite.SQLiteException: [SQLITE_ERROR] SQL error or missing database (near \"selectar\": syntax error)"
+						   : "giis.qacover.portable.QaCoverException: QueryReader.hasRows. Caused by: org.h2.jdbc.JdbcSQLException: Syntax error in SQL statement")
+				: "Giis.Qacover.Portable.QaCoverException: QueryReader.hasRows. Caused by: System.Data.SQLite.SQLiteException: SQL logic error\nnear \"selectar\": syntax error"
 				//: "giis.Qacover.Portable.QaCoverException: SpyStatementAdapter.hasRows. Caused by: Microsoft.Data.Sqlite.SqliteException: SQLite Error 1: 'near \"selectar\": syntax error'."
 				, errorString);
 	}
@@ -205,9 +205,9 @@ public void testMultipleFaultsQuery() throws SQLException {
 	}
 	String exceptionInvalidSql=new Variability().isJava()
 			? (new Variability().isJava8()
-						? "giis.qacover.portable.QaCoverException: SpyStatementAdapter.hasRows. Caused by: org.sqlite.SQLiteException: [SQLITE_ERROR] SQL error or missing database (near \"selectar\": syntax error)"
-						: "giis.qacover.portable.QaCoverException: SpyStatementAdapter.hasRows. Caused by: org.h2.jdbc.JdbcSQLException: Syntax error in SQL statement")
-			: "Giis.Qacover.Portable.QaCoverException: SpyStatementAdapter.hasRows. Caused by: System.Data.SQLite.SQLiteException: SQL logic error\nnear \"selectar\": syntax error"
+						? "giis.qacover.portable.QaCoverException: QueryReader.hasRows. Caused by: org.sqlite.SQLiteException: [SQLITE_ERROR] SQL error or missing database (near \"selectar\": syntax error)"
+						: "giis.qacover.portable.QaCoverException: QueryReader.hasRows. Caused by: org.h2.jdbc.JdbcSQLException: Syntax error in SQL statement")
+			: "Giis.Qacover.Portable.QaCoverException: QueryReader.hasRows. Caused by: System.Data.SQLite.SQLiteException: SQL logic error\nnear \"selectar\": syntax error"
 			//: "giis.Qacover.Portable.QaCoverException: SpyStatementAdapter.hasRows. Caused by: Microsoft.Data.Sqlite.SqliteException: SQLite Error 1: 'near \"selectar\": syntax error'."
 			;
 
diff --git a/qacover-core/src/test/java/test4giis/qacover/TestMutationEvaluation.java b/qacover-core/src/test/java/test4giis/qacover/TestMutationEvaluation.java
new file mode 100644
index 0000000..f257cce
--- /dev/null
+++ b/qacover-core/src/test/java/test4giis/qacover/TestMutationEvaluation.java
@@ -0,0 +1,105 @@
+package test4giis.qacover;
+
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertTrue;
+
+import java.sql.SQLException;
+import java.util.ArrayList;
+import java.util.List;
+
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+
+import giis.qacover.driver.QueryReader;
+import giis.qacover.model.Variability;
+import test4giis.qacoverapp.AppSimpleJdbc;
+
+public class TestMutationEvaluation extends Base {
+	private AppSimpleJdbc app;
+
+	@Before
+	public void setUp() throws SQLException {
+		super.setUp();
+		app = new AppSimpleJdbc(variant);
+		setUpTestData();
+	}
+
+	@After
+	public void tearDown() throws SQLException {
+		super.tearDown();
+		app.close();
+	}
+
+	public void setUpTestData() {
+		app.dropTable("test");
+		app.executeUpdateNative(new String[] { 
+				"create table test(id int, text varchar(16))",
+				"insert into test(id,text) values(1,'abc')", 
+				"insert into test(id,text) values(2,null)" 
+				});
+	}
+
+	@Test
+	public void testEvalMutants() throws SQLException {
+		configureTestOptions().setRuleServiceType("mutation")
+			.setFpcServiceOptions("nomutate=equivalent,ir,abs,uoi,lcr,nl");
+		rs = app.queryMutParameters("abc");
+		assertEvalResults("select id,text from test where text=?", "1 abc", SqlUtil.resultSet2csv(rs, " "),
+				"UNCOVERED SELECT DISTINCT id , text FROM test WHERE text = 'abc'\n"
+						+ "COVERED   SELECT id , text FROM test WHERE text <> 'abc'\n"
+						+ "COVERED   SELECT id , text FROM test WHERE text > 'abc'\n"
+						+ "COVERED   SELECT id , text FROM test WHERE text < 'abc'\n"
+						+ "UNCOVERED SELECT id , text FROM test WHERE text >= 'abc'\n"
+						+ "UNCOVERED SELECT id , text FROM test WHERE text <= 'abc'\n"
+						+ "UNCOVERED SELECT id , text FROM test WHERE (1=1)\n"
+						+ "COVERED   SELECT id , text FROM test WHERE (1=0)",
+				"{?1?='abc'}", false, new Variability().isNetCore());
+	}
+
+	// Detailed evaluation of differences
+	@Test
+	public void testDataCompare() throws SQLException {
+		QueryReader reader = new QueryReader(app.getConnectionNative(), "select id,text from test order by id");
+
+		// equality
+		List<String[]> rows = reader.getRows();
+		assertTrue(reader.equalRows(getList()));
+		assertTrue(reader.equalRows(rows));
+
+		// differences in row sizes
+		rows = getList();
+		rows.remove(1);
+		assertFalse(reader.equalRows(rows));
+		rows = getList();
+		rows.add(new String[] { "3", "zzz" });
+		assertFalse(reader.equalRows(rows));
+
+		// differences in col sizes
+		rows = getList();
+		rows.set(0, new String[] { "1", "abc", "def" });
+		assertFalse(reader.equalRows(rows));
+		rows = getList();
+		rows.set(1, new String[] { "2" });
+		assertFalse(reader.equalRows(rows));
+
+		// Difference in values not null, null and not null, not null and null
+		rows = getList();
+		rows.get(0)[1] = "abcd";
+		assertFalse(reader.equalRows(rows));
+		rows = getList();
+		rows.get(1)[1] = "xyz";
+		assertFalse(reader.equalRows(rows));
+		rows = getList();
+		rows.get(0)[0] = null;
+		assertFalse(reader.equalRows(rows));
+	}
+
+	private List<String[]> getList() {
+		List<String[]> lst = new ArrayList<>();
+		lst.add(new String[] { "1", "abc" });
+		lst.add(new String[] { "2", null });
+		return lst;
+	}
+
+}
diff --git a/qacover-core/src/test/java/test4giis/qacoverapp/AppBase.java b/qacover-core/src/test/java/test4giis/qacoverapp/AppBase.java
index b07d567..a07ed29 100644
--- a/qacover-core/src/test/java/test4giis/qacoverapp/AppBase.java
+++ b/qacover-core/src/test/java/test4giis/qacoverapp/AppBase.java
@@ -203,4 +203,13 @@ public static String jdbcParamsToAssert(String sql, int paramCount) { //NOSONAR
 	public StackLocator myGetStackTraceIgnoredMethod() {
 		return new StackLocator();
 	}
+	
+	public Connection getConnectionNative() throws SQLException {
+		return cf.getNativeConnection();
+	}
+	public ResultSet queryMutParameters(String param1) throws SQLException {
+		PreparedStatement pstmt = conn.prepareStatement("select id,text from test where text=?");
+		pstmt.setString(1, param1);
+		return pstmt.executeQuery();
+	}
 }
diff --git a/qacover-core/src/test/resources/qacover-report/all-data-by-run-order.txt b/qacover-core/src/test/resources/qacover-report/all-data-by-run-order.txt
index 6b29e25..1d357a8 100644
--- a/qacover-core/src/test/resources/qacover-report/all-data-by-run-order.txt
+++ b/qacover-core/src/test/resources/qacover-report/all-data-by-run-order.txt
@@ -457,7 +457,7 @@ rule0: <fpcrule count="1" error="1"><id>1</id><category>S</category><type>B</typ
     <description>--Some row in the table such that:
 --The WHERE condition fulfills:
   --(B+) num = 12</description>
-    <error>giis.qacover.portable.QaCoverException: SpyStatementAdapter.hasRows. Caused by: org.sqlite.SQLiteException: [SQLITE_ERROR] SQL error or missing database (near "selectar": syntax error)</error>
+    <error>giis.qacover.portable.QaCoverException: QueryReader.hasRows. Caused by: org.sqlite.SQLiteException: [SQLITE_ERROR] SQL error or missing database (near "selectar": syntax error)</error>
   </fpcrule>
 rule1: <fpcrule count="1" dead="0"><id>2</id><category>S</category><type>B</type><subtype>B=F</subtype><location>1.w.1.[WHERE num &lt; 11]</location>
     <sql>SELECT id , num , text FROM test WHERE (num = 11)</sql>
@@ -486,8 +486,8 @@ rule0: <fpcrule count="3" error="3"><id>1</id><category>S</category><type>B</typ
     <description>--Some row in the table such that:
 --The WHERE condition fulfills:
   --(B+) num = 10</description>
-    <error>giis.qacover.portable.QaCoverException: SpyStatementAdapter.hasRows. Caused by: org.sqlite.SQLiteException: [SQLITE_ERROR] SQL error or missing database (near "selectar": syntax error)
-giis.qacover.portable.QaCoverException: SpyStatementAdapter.hasRows. Caused by: org.sqlite.SQLiteException: [SQLITE_ERROR] SQL error or missing database (no such table: notable)</error>
+    <error>giis.qacover.portable.QaCoverException: QueryReader.hasRows. Caused by: org.sqlite.SQLiteException: [SQLITE_ERROR] SQL error or missing database (near "selectar": syntax error)
+giis.qacover.portable.QaCoverException: QueryReader.hasRows. Caused by: org.sqlite.SQLiteException: [SQLITE_ERROR] SQL error or missing database (no such table: notable)</error>
   </fpcrule>
 rule1: <fpcrule count="3" dead="0"><id>2</id><category>S</category><type>B</type><subtype>B=F</subtype><location>1.w.1.[WHERE num &lt; 9]</location>
     <sql>SELECT id , num , text FROM test WHERE (num = 9)</sql>
@@ -516,8 +516,8 @@ rule0: <fpcrule count="3" error="3"><id>1</id><category>S</category><type>B</typ
     <description>--Some row in the table such that:
 --The WHERE condition fulfills:
   --(B+) num = 10</description>
-    <error>giis.qacover.portable.QaCoverException: SpyStatementAdapter.hasRows. Caused by: org.sqlite.SQLiteException: [SQLITE_ERROR] SQL error or missing database (near "selectar": syntax error)
-giis.qacover.portable.QaCoverException: SpyStatementAdapter.hasRows. Caused by: org.sqlite.SQLiteException: [SQLITE_ERROR] SQL error or missing database (no such table: notable)</error>
+    <error>giis.qacover.portable.QaCoverException: QueryReader.hasRows. Caused by: org.sqlite.SQLiteException: [SQLITE_ERROR] SQL error or missing database (near "selectar": syntax error)
+giis.qacover.portable.QaCoverException: QueryReader.hasRows. Caused by: org.sqlite.SQLiteException: [SQLITE_ERROR] SQL error or missing database (no such table: notable)</error>
   </fpcrule>
 rule1: <fpcrule count="3" dead="0"><id>2</id><category>S</category><type>B</type><subtype>B=F</subtype><location>1.w.1.[WHERE num &lt; 9]</location>
     <sql>SELECT id , num , text FROM test WHERE (num = 9)</sql>
@@ -546,8 +546,8 @@ rule0: <fpcrule count="3" error="3"><id>1</id><category>S</category><type>B</typ
     <description>--Some row in the table such that:
 --The WHERE condition fulfills:
   --(B+) num = 10</description>
-    <error>giis.qacover.portable.QaCoverException: SpyStatementAdapter.hasRows. Caused by: org.sqlite.SQLiteException: [SQLITE_ERROR] SQL error or missing database (near "selectar": syntax error)
-giis.qacover.portable.QaCoverException: SpyStatementAdapter.hasRows. Caused by: org.sqlite.SQLiteException: [SQLITE_ERROR] SQL error or missing database (no such table: notable)</error>
+    <error>giis.qacover.portable.QaCoverException: QueryReader.hasRows. Caused by: org.sqlite.SQLiteException: [SQLITE_ERROR] SQL error or missing database (near "selectar": syntax error)
+giis.qacover.portable.QaCoverException: QueryReader.hasRows. Caused by: org.sqlite.SQLiteException: [SQLITE_ERROR] SQL error or missing database (no such table: notable)</error>
   </fpcrule>
 rule1: <fpcrule count="3" dead="0"><id>2</id><category>S</category><type>B</type><subtype>B=F</subtype><location>1.w.1.[WHERE num &lt; 9]</location>
     <sql>SELECT id , num , text FROM test WHERE (num = 9)</sql>
diff --git a/qacover-core/src/test/resources/qacover-report/test4giis.qacoverapp.AppSimpleJdbc3Errors.html b/qacover-core/src/test/resources/qacover-report/test4giis.qacoverapp.AppSimpleJdbc3Errors.html
index 9d807ba..a62cfd9 100644
--- a/qacover-core/src/test/resources/qacover-report/test4giis.qacoverapp.AppSimpleJdbc3Errors.html
+++ b/qacover-core/src/test/resources/qacover-report/test4giis.qacoverapp.AppSimpleJdbc3Errors.html
@@ -201,7 +201,7 @@ <h4><a href='./index.html'>[Index]</a> test4giis.qacoverapp.AppSimpleJdbc3Errors
             <td class='uncovered'>--Some row in the table such that: <br class='canhide'/>--The WHERE condition fulfills: <br class='canhide'/>  --(B+) num = 12</td>
             <td class='uncovered'>selectar id,num,text from test where num &lt; 9</td>
     </tr>
-    <tr class='rule-error'><td colspan='2'></td><td colspan='2'><span style="color:red;">Rule error: giis.qacover.portable.QaCoverException: SpyStatementAdapter.hasRows. Caused by: org.sqlite.SQLiteException: [SQLITE_ERROR] SQL error or missing database (near "selectar": syntax error)</span></td></tr>
+    <tr class='rule-error'><td colspan='2'></td><td colspan='2'><span style="color:red;">Rule error: giis.qacover.portable.QaCoverException: QueryReader.hasRows. Caused by: org.sqlite.SQLiteException: [SQLITE_ERROR] SQL error or missing database (near "selectar": syntax error)</span></td></tr>
     <tr class='rule-summary'>
         <td></td>
         <td class='coverage' rowspan='2'><strong>2</strong> - dead:&nbsp;0 count:&nbsp;1</td>
@@ -270,8 +270,8 @@ <h4><a href='./index.html'>[Index]</a> test4giis.qacoverapp.AppSimpleJdbc3Errors
             <td class='uncovered'>--Some row in the table such that: <br class='canhide'/>--The WHERE condition fulfills: <br class='canhide'/>  --(B+) num = 10</td>
             <td class='uncovered'>select id,num,text from notable where num &lt; 9</td>
     </tr>
-    <tr class='rule-error'><td colspan='2'></td><td colspan='2'><span style="color:red;">Rule error: giis.qacover.portable.QaCoverException: SpyStatementAdapter.hasRows. Caused by: org.sqlite.SQLiteException: [SQLITE_ERROR] SQL error or missing database (near "selectar": syntax error)
-<br/>giis.qacover.portable.QaCoverException: SpyStatementAdapter.hasRows. Caused by: org.sqlite.SQLiteException: [SQLITE_ERROR] SQL error or missing database (no such table: notable)</span></td></tr>
+    <tr class='rule-error'><td colspan='2'></td><td colspan='2'><span style="color:red;">Rule error: giis.qacover.portable.QaCoverException: QueryReader.hasRows. Caused by: org.sqlite.SQLiteException: [SQLITE_ERROR] SQL error or missing database (near "selectar": syntax error)
+<br/>giis.qacover.portable.QaCoverException: QueryReader.hasRows. Caused by: org.sqlite.SQLiteException: [SQLITE_ERROR] SQL error or missing database (no such table: notable)</span></td></tr>
     <tr class='rule-summary'>
         <td></td>
         <td class='coverage' rowspan='2'><strong>2</strong> - dead:&nbsp;0 count:&nbsp;3</td>
diff --git a/qacover-model/src/main/java/giis/qacover/report/ClassHtmlWriter.java b/qacover-model/src/main/java/giis/qacover/report/ClassHtmlWriter.java
index 24e92c9..7d8362b 100644
--- a/qacover-model/src/main/java/giis/qacover/report/ClassHtmlWriter.java
+++ b/qacover-model/src/main/java/giis/qacover/report/ClassHtmlWriter.java
@@ -172,8 +172,10 @@ public String getRuleContent(RuleModel rule) {
 				+ "    </tr>\n"
 				+ "    <tr class='rule-sql'>\n"
 				+ "        <td></td>\n"
-				+ "            <td class='$ruleStatus$'>$ruleDescription$</td>\n"
-				+ "            <td class='$ruleStatus$'>$ruleSql$</td>\n"
+				+ ("".equals(rule.getDescription())
+				? "            <td class='$ruleStatus$ rowspan='2'>$ruleSql$</td>\n"
+				: "            <td class='$ruleStatus$'>$ruleDescription$</td>\n"
+				+ "            <td class='$ruleStatus$'>$ruleSql$</td>\n")
 				+ "    </tr>\n"
 				// needs a complete row to allow error message span across description and sql columns
 				+ "    $ruleErrors$";