diff --git a/.gitignore b/.gitignore
new file mode 100644
index 000000000..8aca08b4d
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,44 @@
+HELP.md
+.gradle
+build/
+!gradle/wrapper/gradle-wrapper.jar
+!**/src/main/**/build/
+!**/src/test/**/build/
+
+### STS ###
+.apt_generated
+.classpath
+.factorypath
+.project
+.settings
+.springBeans
+.sts4-cache
+bin/
+!**/src/main/**/bin/
+!**/src/test/**/bin/
+
+### IntelliJ IDEA ###
+.idea
+*.iws
+*.iml
+*.ipr
+out/
+!**/src/main/**/out/
+!**/src/test/**/out/
+
+### NetBeans ###
+/nbproject/private/
+/nbbuild/
+/dist/
+/nbdist/
+/.nb-gradle/
+
+### VS Code ###
+.vscode/
+
+
+### application.yml ###
+application.yaml
+
+### DS_Store
+.DS_Store
diff --git a/build.gradle b/build.gradle
new file mode 100644
index 000000000..42a708680
--- /dev/null
+++ b/build.gradle
@@ -0,0 +1,36 @@
+plugins {
+	id 'java'
+	id 'org.springframework.boot' version '3.1.2'
+	id 'io.spring.dependency-management' version '1.1.2'
+}
+
+group = 'com.kdt.lecture'
+version = '0.0.1-SNAPSHOT'
+
+java {
+	sourceCompatibility = '17'
+}
+
+configurations {
+	compileOnly {
+		extendsFrom annotationProcessor
+	}
+}
+
+repositories {
+	mavenCentral()
+}
+
+dependencies {
+	implementation 'org.springframework.boot:spring-boot-starter-data-jpa'
+	implementation 'org.springframework.boot:spring-boot-starter-web'
+	implementation 'org.projectlombok:lombok'
+	annotationProcessor 'org.projectlombok:lombok'
+	testAnnotationProcessor 'org.projectlombok:lombok'
+	testImplementation 'org.springframework.boot:spring-boot-starter-test'
+	runtimeOnly 'com.h2database:h2'
+}
+
+tasks.named('test') {
+	useJUnitPlatform()
+}
diff --git a/gradle/wrapper/gradle-wrapper.jar b/gradle/wrapper/gradle-wrapper.jar
new file mode 100644
index 000000000..c1962a79e
Binary files /dev/null and b/gradle/wrapper/gradle-wrapper.jar differ
diff --git a/gradle/wrapper/gradle-wrapper.properties b/gradle/wrapper/gradle-wrapper.properties
new file mode 100644
index 000000000..37aef8d3f
--- /dev/null
+++ b/gradle/wrapper/gradle-wrapper.properties
@@ -0,0 +1,6 @@
+distributionBase=GRADLE_USER_HOME
+distributionPath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-8.1.1-bin.zip
+networkTimeout=10000
+zipStoreBase=GRADLE_USER_HOME
+zipStorePath=wrapper/dists
diff --git a/gradlew b/gradlew
new file mode 100755
index 000000000..aeb74cbb4
--- /dev/null
+++ b/gradlew
@@ -0,0 +1,245 @@
+#!/bin/sh
+
+#
+# Copyright © 2015-2021 the original authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      https://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+
+##############################################################################
+#
+#   Gradle start up script for POSIX generated by Gradle.
+#
+#   Important for running:
+#
+#   (1) You need a POSIX-compliant shell to run this script. If your /bin/sh is
+#       noncompliant, but you have some other compliant shell such as ksh or
+#       bash, then to run this script, type that shell name before the whole
+#       command line, like:
+#
+#           ksh Gradle
+#
+#       Busybox and similar reduced shells will NOT work, because this script
+#       requires all of these POSIX shell features:
+#         * functions;
+#         * expansions «$var», «${var}», «${var:-default}», «${var+SET}»,
+#           «${var#prefix}», «${var%suffix}», and «$( cmd )»;
+#         * compound commands having a testable exit status, especially «case»;
+#         * various built-in commands including «command», «set», and «ulimit».
+#
+#   Important for patching:
+#
+#   (2) This script targets any POSIX shell, so it avoids extensions provided
+#       by Bash, Ksh, etc; in particular arrays are avoided.
+#
+#       The "traditional" practice of packing multiple parameters into a
+#       space-separated string is a well documented source of bugs and security
+#       problems, so this is (mostly) avoided, by progressively accumulating
+#       options in "$@", and eventually passing that to Java.
+#
+#       Where the inherited environment variables (DEFAULT_JVM_OPTS, JAVA_OPTS,
+#       and GRADLE_OPTS) rely on word-splitting, this is performed explicitly;
+#       see the in-line comments for details.
+#
+#       There are tweaks for specific operating systems such as AIX, CygWin,
+#       Darwin, MinGW, and NonStop.
+#
+#   (3) This script is generated from the Groovy template
+#       https://github.com/gradle/gradle/blob/HEAD/subprojects/plugins/src/main/resources/org/gradle/api/internal/plugins/unixStartScript.txt
+#       within the Gradle project.
+#
+#       You can find Gradle at https://github.com/gradle/gradle/.
+#
+##############################################################################
+
+# Attempt to set APP_HOME
+
+# Resolve links: $0 may be a link
+app_path=$0
+
+# Need this for daisy-chained symlinks.
+while
+    APP_HOME=${app_path%"${app_path##*/}"}  # leaves a trailing /; empty if no leading path
+    [ -h "$app_path" ]
+do
+    ls=$( ls -ld "$app_path" )
+    link=${ls#*' -> '}
+    case $link in             #(
+      /*)   app_path=$link ;; #(
+      *)    app_path=$APP_HOME$link ;;
+    esac
+done
+
+# This is normally unused
+# shellcheck disable=SC2034
+APP_BASE_NAME=${0##*/}
+APP_HOME=$( cd "${APP_HOME:-./}" && pwd -P ) || exit
+
+# Use the maximum available, or set MAX_FD != -1 to use that value.
+MAX_FD=maximum
+
+warn () {
+    echo "$*"
+} >&2
+
+die () {
+    echo
+    echo "$*"
+    echo
+    exit 1
+} >&2
+
+# OS specific support (must be 'true' or 'false').
+cygwin=false
+msys=false
+darwin=false
+nonstop=false
+case "$( uname )" in                #(
+  CYGWIN* )         cygwin=true  ;; #(
+  Darwin* )         darwin=true  ;; #(
+  MSYS* | MINGW* )  msys=true    ;; #(
+  NONSTOP* )        nonstop=true ;;
+esac
+
+CLASSPATH=$APP_HOME/gradle/wrapper/gradle-wrapper.jar
+
+
+# Determine the Java command to use to start the JVM.
+if [ -n "$JAVA_HOME" ] ; then
+    if [ -x "$JAVA_HOME/jre/sh/java" ] ; then
+        # IBM's JDK on AIX uses strange locations for the executables
+        JAVACMD=$JAVA_HOME/jre/sh/java
+    else
+        JAVACMD=$JAVA_HOME/bin/java
+    fi
+    if [ ! -x "$JAVACMD" ] ; then
+        die "ERROR: JAVA_HOME is set to an invalid directory: $JAVA_HOME
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+    fi
+else
+    JAVACMD=java
+    which java >/dev/null 2>&1 || die "ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+fi
+
+# Increase the maximum file descriptors if we can.
+if ! "$cygwin" && ! "$darwin" && ! "$nonstop" ; then
+    case $MAX_FD in #(
+      max*)
+        # In POSIX sh, ulimit -H is undefined. That's why the result is checked to see if it worked.
+        # shellcheck disable=SC3045
+        MAX_FD=$( ulimit -H -n ) ||
+            warn "Could not query maximum file descriptor limit"
+    esac
+    case $MAX_FD in  #(
+      '' | soft) :;; #(
+      *)
+        # In POSIX sh, ulimit -n is undefined. That's why the result is checked to see if it worked.
+        # shellcheck disable=SC3045
+        ulimit -n "$MAX_FD" ||
+            warn "Could not set maximum file descriptor limit to $MAX_FD"
+    esac
+fi
+
+# Collect all arguments for the java command, stacking in reverse order:
+#   * args from the command line
+#   * the main class name
+#   * -classpath
+#   * -D...appname settings
+#   * --module-path (only if needed)
+#   * DEFAULT_JVM_OPTS, JAVA_OPTS, and GRADLE_OPTS environment variables.
+
+# For Cygwin or MSYS, switch paths to Windows format before running java
+if "$cygwin" || "$msys" ; then
+    APP_HOME=$( cygpath --path --mixed "$APP_HOME" )
+    CLASSPATH=$( cygpath --path --mixed "$CLASSPATH" )
+
+    JAVACMD=$( cygpath --unix "$JAVACMD" )
+
+    # Now convert the arguments - kludge to limit ourselves to /bin/sh
+    for arg do
+        if
+            case $arg in                                #(
+              -*)   false ;;                            # don't mess with options #(
+              /?*)  t=${arg#/} t=/${t%%/*}              # looks like a POSIX filepath
+                    [ -e "$t" ] ;;                      #(
+              *)    false ;;
+            esac
+        then
+            arg=$( cygpath --path --ignore --mixed "$arg" )
+        fi
+        # Roll the args list around exactly as many times as the number of
+        # args, so each arg winds up back in the position where it started, but
+        # possibly modified.
+        #
+        # NB: a `for` loop captures its iteration list before it begins, so
+        # changing the positional parameters here affects neither the number of
+        # iterations, nor the values presented in `arg`.
+        shift                   # remove old arg
+        set -- "$@" "$arg"      # push replacement arg
+    done
+fi
+
+
+# Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+DEFAULT_JVM_OPTS='"-Xmx64m" "-Xms64m"'
+
+# Collect all arguments for the java command;
+#   * $DEFAULT_JVM_OPTS, $JAVA_OPTS, and $GRADLE_OPTS can contain fragments of
+#     shell script including quotes and variable substitutions, so put them in
+#     double quotes to make sure that they get re-expanded; and
+#   * put everything else in single quotes, so that it's not re-expanded.
+
+set -- \
+        "-Dorg.gradle.appname=$APP_BASE_NAME" \
+        -classpath "$CLASSPATH" \
+        org.gradle.wrapper.GradleWrapperMain \
+        "$@"
+
+# Stop when "xargs" is not available.
+if ! command -v xargs >/dev/null 2>&1
+then
+    die "xargs is not available"
+fi
+
+# Use "xargs" to parse quoted args.
+#
+# With -n1 it outputs one arg per line, with the quotes and backslashes removed.
+#
+# In Bash we could simply go:
+#
+#   readarray ARGS < <( xargs -n1 <<<"$var" ) &&
+#   set -- "${ARGS[@]}" "$@"
+#
+# but POSIX shell has neither arrays nor command substitution, so instead we
+# post-process each arg (as a line of input to sed) to backslash-escape any
+# character that might be a shell metacharacter, then use eval to reverse
+# that process (while maintaining the separation between arguments), and wrap
+# the whole thing up as a single "set" statement.
+#
+# This will of course break if any of these variables contains a newline or
+# an unmatched quote.
+#
+
+eval "set -- $(
+        printf '%s\n' "$DEFAULT_JVM_OPTS $JAVA_OPTS $GRADLE_OPTS" |
+        xargs -n1 |
+        sed ' s~[^-[:alnum:]+,./:=@_]~\\&~g; ' |
+        tr '\n' ' '
+    )" '"$@"'
+
+exec "$JAVACMD" "$@"
diff --git a/gradlew.bat b/gradlew.bat
new file mode 100644
index 000000000..6689b85be
--- /dev/null
+++ b/gradlew.bat
@@ -0,0 +1,92 @@
+@rem
+@rem Copyright 2015 the original author or authors.
+@rem
+@rem Licensed under the Apache License, Version 2.0 (the "License");
+@rem you may not use this file except in compliance with the License.
+@rem You may obtain a copy of the License at
+@rem
+@rem      https://www.apache.org/licenses/LICENSE-2.0
+@rem
+@rem Unless required by applicable law or agreed to in writing, software
+@rem distributed under the License is distributed on an "AS IS" BASIS,
+@rem WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+@rem See the License for the specific language governing permissions and
+@rem limitations under the License.
+@rem
+
+@if "%DEBUG%"=="" @echo off
+@rem ##########################################################################
+@rem
+@rem  Gradle startup script for Windows
+@rem
+@rem ##########################################################################
+
+@rem Set local scope for the variables with windows NT shell
+if "%OS%"=="Windows_NT" setlocal
+
+set DIRNAME=%~dp0
+if "%DIRNAME%"=="" set DIRNAME=.
+@rem This is normally unused
+set APP_BASE_NAME=%~n0
+set APP_HOME=%DIRNAME%
+
+@rem Resolve any "." and ".." in APP_HOME to make it shorter.
+for %%i in ("%APP_HOME%") do set APP_HOME=%%~fi
+
+@rem Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+set DEFAULT_JVM_OPTS="-Xmx64m" "-Xms64m"
+
+@rem Find java.exe
+if defined JAVA_HOME goto findJavaFromJavaHome
+
+set JAVA_EXE=java.exe
+%JAVA_EXE% -version >NUL 2>&1
+if %ERRORLEVEL% equ 0 goto execute
+
+echo.
+echo ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+echo.
+echo Please set the JAVA_HOME variable in your environment to match the
+echo location of your Java installation.
+
+goto fail
+
+:findJavaFromJavaHome
+set JAVA_HOME=%JAVA_HOME:"=%
+set JAVA_EXE=%JAVA_HOME%/bin/java.exe
+
+if exist "%JAVA_EXE%" goto execute
+
+echo.
+echo ERROR: JAVA_HOME is set to an invalid directory: %JAVA_HOME%
+echo.
+echo Please set the JAVA_HOME variable in your environment to match the
+echo location of your Java installation.
+
+goto fail
+
+:execute
+@rem Setup the command line
+
+set CLASSPATH=%APP_HOME%\gradle\wrapper\gradle-wrapper.jar
+
+
+@rem Execute Gradle
+"%JAVA_EXE%" %DEFAULT_JVM_OPTS% %JAVA_OPTS% %GRADLE_OPTS% "-Dorg.gradle.appname=%APP_BASE_NAME%" -classpath "%CLASSPATH%" org.gradle.wrapper.GradleWrapperMain %*
+
+:end
+@rem End local scope for the variables with windows NT shell
+if %ERRORLEVEL% equ 0 goto mainEnd
+
+:fail
+rem Set variable GRADLE_EXIT_CONSOLE if you need the _script_ return code instead of
+rem the _cmd.exe /c_ return code!
+set EXIT_CODE=%ERRORLEVEL%
+if %EXIT_CODE% equ 0 set EXIT_CODE=1
+if not ""=="%GRADLE_EXIT_CONSOLE%" exit %EXIT_CODE%
+exit /b %EXIT_CODE%
+
+:mainEnd
+if "%OS%"=="Windows_NT" endlocal
+
+:omega
diff --git a/settings.gradle b/settings.gradle
new file mode 100644
index 000000000..0be280ea9
--- /dev/null
+++ b/settings.gradle
@@ -0,0 +1 @@
+rootProject.name = 'LectureJpa'
diff --git a/src/main/java/com/kdt/lecture/LectureJpaApplication.java b/src/main/java/com/kdt/lecture/LectureJpaApplication.java
new file mode 100644
index 000000000..aab11dce8
--- /dev/null
+++ b/src/main/java/com/kdt/lecture/LectureJpaApplication.java
@@ -0,0 +1,13 @@
+package com.kdt.lecture;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+
+@SpringBootApplication
+public class LectureJpaApplication {
+
+	public static void main(String[] args) {
+		SpringApplication.run(LectureJpaApplication.class, args);
+	}
+
+}
diff --git a/src/main/java/com/kdt/lecture/config/DataSourceConfig.java b/src/main/java/com/kdt/lecture/config/DataSourceConfig.java
new file mode 100644
index 000000000..e59599792
--- /dev/null
+++ b/src/main/java/com/kdt/lecture/config/DataSourceConfig.java
@@ -0,0 +1,65 @@
+package com.kdt.lecture.config;
+
+import org.springframework.boot.autoconfigure.orm.jpa.JpaProperties;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.data.jpa.repository.config.EnableJpaRepositories;
+import org.springframework.jdbc.datasource.DriverManagerDataSource;
+import org.springframework.orm.jpa.JpaTransactionManager;
+import org.springframework.orm.jpa.JpaVendorAdapter;
+import org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean;
+import org.springframework.orm.jpa.vendor.AbstractJpaVendorAdapter;
+import org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter;
+import org.springframework.transaction.PlatformTransactionManager;
+
+import javax.sql.DataSource;
+import java.util.Properties;
+
+@Configuration
+@EnableJpaRepositories(basePackages = "com.kdt.lecture.domain")
+public class DataSourceConfig {
+
+    @Bean
+    public DataSource dataSource() {
+        DriverManagerDataSource dataSource = new DriverManagerDataSource();
+        dataSource.setDriverClassName("org.h2.Driver");
+        dataSource.setUrl("jdbc:h2:~/test");
+        dataSource.setUsername("sa");
+        dataSource.setPassword("");
+
+        return dataSource;
+    }
+
+    @Bean
+    public JpaVendorAdapter jpaVendorAdapter(JpaProperties jpaProperties) {
+        AbstractJpaVendorAdapter adapter = new HibernateJpaVendorAdapter();
+        adapter.setShowSql(jpaProperties.isShowSql());
+        adapter.setDatabasePlatform(jpaProperties.getDatabasePlatform());
+        adapter.setGenerateDdl(jpaProperties.isGenerateDdl());
+        return adapter;
+    }
+
+    @Bean
+    public LocalContainerEntityManagerFactoryBean entityManagerFactory(DataSource dataSource, JpaVendorAdapter jpaVendorAdapter,
+                                                                       JpaProperties jpaProperties) {
+        LocalContainerEntityManagerFactoryBean em
+                = new LocalContainerEntityManagerFactoryBean();
+        em.setDataSource(dataSource);
+        em.setPackagesToScan("com.kdt.lecture.domain");
+        em.setJpaVendorAdapter(jpaVendorAdapter);
+
+        Properties properties = new Properties();
+        properties.putAll(jpaProperties.getProperties());
+        em.setJpaProperties(properties);
+
+        return em;
+    }
+
+    @Bean
+    public PlatformTransactionManager transactionManager(LocalContainerEntityManagerFactoryBean entityManagerFactory) {
+        JpaTransactionManager transactionManager = new JpaTransactionManager();
+        transactionManager.setEntityManagerFactory(entityManagerFactory.getObject());
+
+        return transactionManager;
+    }
+}
diff --git a/src/main/java/com/kdt/lecture/domain/Customer.java b/src/main/java/com/kdt/lecture/domain/Customer.java
new file mode 100644
index 000000000..612523d33
--- /dev/null
+++ b/src/main/java/com/kdt/lecture/domain/Customer.java
@@ -0,0 +1,40 @@
+package com.kdt.lecture.domain;
+
+import jakarta.persistence.*;
+import lombok.AccessLevel;
+import lombok.Builder;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+
+import java.util.ArrayList;
+import java.util.List;
+
+@Getter
+@Entity
+@Table(name = "customers")
+@NoArgsConstructor(access = AccessLevel.PROTECTED)
+public class Customer {
+    @Id
+    @GeneratedValue(strategy = GenerationType.SEQUENCE)
+    private Long id;
+
+    @Column(nullable = false)
+    private String firstName;
+
+    @Column(nullable = false)
+    private String lastName;
+
+    @OneToMany(mappedBy = "customer", fetch = FetchType.LAZY, cascade = CascadeType.ALL, orphanRemoval = true)
+    private List<Order> orders = new ArrayList<>();
+
+    @Builder
+    public Customer(String firstName, String lastName) {
+        this.firstName = firstName;
+        this.lastName = lastName;
+    }
+
+    public void updateCustomerName(String firstName, String lastName) {
+        this.firstName = firstName;
+        this.lastName = lastName;
+    }
+}
\ No newline at end of file
diff --git a/src/main/java/com/kdt/lecture/domain/CustomerRepository.java b/src/main/java/com/kdt/lecture/domain/CustomerRepository.java
new file mode 100644
index 000000000..178b28ffc
--- /dev/null
+++ b/src/main/java/com/kdt/lecture/domain/CustomerRepository.java
@@ -0,0 +1,6 @@
+package com.kdt.lecture.domain;
+
+import org.springframework.data.jpa.repository.JpaRepository;
+
+public interface CustomerRepository extends JpaRepository<Customer, Long> {
+}
diff --git a/src/main/java/com/kdt/lecture/domain/Item.java b/src/main/java/com/kdt/lecture/domain/Item.java
new file mode 100644
index 000000000..886cfa8a5
--- /dev/null
+++ b/src/main/java/com/kdt/lecture/domain/Item.java
@@ -0,0 +1,45 @@
+package com.kdt.lecture.domain;
+
+import jakarta.persistence.*;
+import lombok.AccessLevel;
+import lombok.Builder;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+
+import java.util.Objects;
+
+@Getter
+@Entity
+@Table(name = "items")
+@NoArgsConstructor(access = AccessLevel.PROTECTED)
+public class Item {
+    @Id
+    @GeneratedValue(strategy = GenerationType.SEQUENCE)
+    private Long id;
+
+    @Column(name = "price", nullable = false)
+    private int price;
+
+    @Column(name = "stock_quantity", nullable = false)
+    private int stockQuantity;
+
+    @ManyToOne(fetch = FetchType.EAGER)
+    @JoinColumn(name = "order_item_id", referencedColumnName = "id")
+    private OrderItem orderItem;
+
+    @Builder
+    public Item(int price, int stockQuantity, OrderItem orderItem) {
+        this.price = price;
+        this.stockQuantity = stockQuantity;
+        setOrderItem(orderItem);
+    }
+
+    private void setOrderItem(OrderItem orderItem) {
+        if (Objects.nonNull(this.orderItem)) {
+            this.orderItem.getItems().remove(this);
+        }
+
+        this.orderItem = orderItem;
+        orderItem.getItems().add(this);
+    }
+}
diff --git a/src/main/java/com/kdt/lecture/domain/Order.java b/src/main/java/com/kdt/lecture/domain/Order.java
new file mode 100644
index 000000000..2e01f69b6
--- /dev/null
+++ b/src/main/java/com/kdt/lecture/domain/Order.java
@@ -0,0 +1,43 @@
+package com.kdt.lecture.domain;
+
+import jakarta.persistence.*;
+import lombok.*;
+
+import java.time.LocalDateTime;
+import java.util.List;
+
+@Getter
+@Entity
+@Table(name = "orders")
+@NoArgsConstructor(access = AccessLevel.PROTECTED)
+public class Order {
+    @Id
+    @GeneratedValue(strategy = GenerationType.SEQUENCE)
+    private Long id;
+
+    @Column(name = "memo", nullable = true)
+    @Setter
+    private String memo;
+
+    @Enumerated(value = EnumType.STRING)
+    @Column(nullable = false)
+    private OrderStatus orderStatus;
+
+    @Column(name = "order_date_time", columnDefinition = "TIMESTAMP", nullable = false)
+    private LocalDateTime orderDateTime;
+
+    @ManyToOne(fetch = FetchType.EAGER)
+    @JoinColumn(name = "customer_id", referencedColumnName = "id", nullable = false)
+    private Customer customer;
+
+    @OneToMany(mappedBy = "order", fetch = FetchType.LAZY, cascade = CascadeType.ALL, orphanRemoval = true)
+    private List<OrderItem> orderItems;
+
+    @Builder
+    public Order(OrderStatus orderStatus, LocalDateTime orderDateTime, Customer customer) {
+        this.orderStatus = orderStatus;
+        this.orderDateTime = orderDateTime;
+        this.customer = customer;
+    }
+
+}
diff --git a/src/main/java/com/kdt/lecture/domain/OrderItem.java b/src/main/java/com/kdt/lecture/domain/OrderItem.java
new file mode 100644
index 000000000..3c7c36dc0
--- /dev/null
+++ b/src/main/java/com/kdt/lecture/domain/OrderItem.java
@@ -0,0 +1,48 @@
+package com.kdt.lecture.domain;
+
+import jakarta.persistence.*;
+import lombok.AccessLevel;
+import lombok.Builder;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+
+import java.util.List;
+import java.util.Objects;
+
+@Getter
+@Entity
+@Table(name = "order_item")
+@NoArgsConstructor(access = AccessLevel.PROTECTED)
+public class OrderItem {
+    @Id
+    @GeneratedValue(strategy = GenerationType.SEQUENCE)
+    private Long id;
+
+    @Column(name = "price", nullable = false)
+    private int price;
+
+    @Column(name = "quantity", nullable = false)
+    private int quantity;
+
+    @ManyToOne(fetch = FetchType.EAGER)
+    @JoinColumn(name = "order_id", referencedColumnName = "id")
+    private Order order;
+
+    @OneToMany(mappedBy = "orderItems", fetch = FetchType.LAZY, cascade = CascadeType.ALL, orphanRemoval = true)
+    private List<Item> items;
+
+    @Builder
+    public OrderItem(int price, int quantity, Order order) {
+        this.price = price;
+        this.quantity = quantity;
+        setOrder(order);
+    }
+
+    private void setOrder(Order order) {
+        if (Objects.nonNull(this.order)) {
+            this.order.getOrderItems().remove(this);
+        }
+        this.order = order;
+        order.getOrderItems().add(this);
+    }
+}
diff --git a/src/main/java/com/kdt/lecture/domain/OrderStatus.java b/src/main/java/com/kdt/lecture/domain/OrderStatus.java
new file mode 100644
index 000000000..d0e92bfbb
--- /dev/null
+++ b/src/main/java/com/kdt/lecture/domain/OrderStatus.java
@@ -0,0 +1,5 @@
+package com.kdt.lecture.domain;
+
+public enum OrderStatus {
+    OPENED, CANCELLED
+}
\ No newline at end of file
diff --git a/src/test/java/com/kdt/lecture/LectureJpaApplicationTests.java b/src/test/java/com/kdt/lecture/LectureJpaApplicationTests.java
new file mode 100644
index 000000000..ef7275823
--- /dev/null
+++ b/src/test/java/com/kdt/lecture/LectureJpaApplicationTests.java
@@ -0,0 +1,13 @@
+package com.kdt.lecture;
+
+import org.junit.jupiter.api.Test;
+import org.springframework.boot.test.context.SpringBootTest;
+
+@SpringBootTest
+class LectureJpaApplicationTests {
+
+	@Test
+	void contextLoads() {
+	}
+
+}
diff --git a/src/test/java/com/kdt/lecture/domain/CustomerRepositoryTest.java b/src/test/java/com/kdt/lecture/domain/CustomerRepositoryTest.java
new file mode 100644
index 000000000..0e7eed7b7
--- /dev/null
+++ b/src/test/java/com/kdt/lecture/domain/CustomerRepositoryTest.java
@@ -0,0 +1,33 @@
+package com.kdt.lecture.domain;
+
+import lombok.extern.slf4j.Slf4j;
+import org.junit.jupiter.api.Test;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.context.SpringBootTest;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+@Slf4j
+@SpringBootTest
+class CustomerRepositoryTest {
+
+    @Autowired
+    private CustomerRepository repository;
+
+    @Test
+    void test() {
+        // Given
+        Customer customer = new Customer();
+        customer.setId(1L);
+        customer.setFirstName("honggu");
+        customer.setLastName("Kang");
+//        customer.setAge(33);
+
+        // When
+        repository.save(customer);
+
+        // Then
+        Customer entity = repository.findById(1L).get();
+        log.info("{} {}", entity.getLastName(), entity.getFirstName());
+    }
+}
\ No newline at end of file