\uc2a4\ud504\ub9c1 \ubd80\ud2b8\ub294 \uc790\ubc14 \uae30\ubc18\uc758 \uc560\ud50c\ub9ac\ucf00\uc774\uc158\uc744 \uc27d\uac8c \ub9cc\ub4e4 \uc218 \uc788\ub3c4\ub85d \ub3c4\uc640\uc8fc\ub294 \ud504\ub808\uc784\uc6cc\ud06c\uc785\ub2c8\ub2e4. \ud2b9\ud788 \ubc31\uc5d4\ub4dc \uac1c\ubc1c\uc744 \ud560 \ub54c, \ub370\uc774\ud130\ubca0\uc774\uc2a4\uc640\uc758 \uc0c1\ud638\uc791\uc6a9\uc774 \ud544\uc218\uc801\uc774\uba70, \uc774\ub54c \uc601\uc18d\uc131 \ucee8\ud14d\uc2a4\ud2b8(Persistence Context)\uc758 \uac1c\ub150\uc740 \ub9e4\uc6b0 \uc911\uc694\ud569\ub2c8\ub2e4. \uc774 \uae00\uc5d0\uc11c\ub294 \uc601\uc18d\uc131 \ucee8\ud14d\uc2a4\ud2b8\uac00 \ubb34\uc5c7\uc778\uc9c0, \uc5b4\ub5bb\uac8c \uc791\ub3d9\ud558\ub294\uc9c0, \uadf8\ub9ac\uace0 \uc774\ub97c \uc2a4\ud504\ub9c1 \ubd80\ud2b8\ub97c \ud1b5\ud574 \uc5b4\ub5bb\uac8c \ud65c\uc6a9\ud560 \uc218 \uc788\ub294\uc9c0\uc5d0 \ub300\ud574 \uc0c1\uc138\ud788 \uc54c\uc544\ubcf4\uaca0\uc2b5\ub2c8\ub2e4.<\/p>\n
\uc601\uc18d\uc131 \ucee8\ud14d\uc2a4\ud2b8\ub294 \uc5d4\ud2f0\ud2f0\uc758 \uc0dd\uba85 \uc8fc\uae30\ub97c \uad00\ub9ac\ud558\ub294 \ud658\uacbd\uc785\ub2c8\ub2e4. \uc774\ub294 \ub370\uc774\ud130\ubca0\uc774\uc2a4\uc640 \uc5d4\ud2f0\ud2f0(\uc989, \uc790\ubc14 \uac1d\uccb4) \uac04\uc758 \ub9e4\ud551\uc744 \ub2e4\ub8e8\uba70, \uc5d4\ud2f0\ud2f0\uc758 \uc0c1\ud0dc\ub97c \uc720\uc9c0\ud558\uace0 \ubcc0\uacbd \uc0ac\ud56d\uc744 \ucd94\uc801\ud558\ub294 \uc5ed\ud560\uc744 \ud569\ub2c8\ub2e4. \uc601\uc18d\uc131 \ucee8\ud14d\uc2a4\ud2b8\ub294 \ud06c\uac8c **\uc601\uc18d\uc131 \uc800\uc7a5\uc18c**\uc640 **\ubcc0\uacbd \uac10\uc9c0**\ub97c \ud1b5\ud574 \uc774\ub8e8\uc5b4\uc9d1\ub2c8\ub2e4.<\/p>\n
\uc5d4\ud2f0\ud2f0\ub294 \ub2e4\uc74c\uacfc \uac19\uc740 \ub124 \uac00\uc9c0 \uc0c1\ud0dc\ub97c \uac00\uc9d1\ub2c8\ub2e4.<\/p>\n
\uc601\uc18d\uc131 \ucee8\ud14d\uc2a4\ud2b8\ub294 \uad00\ub9ac\ud558\ub294 \ubaa8\ub4e0 \uc5d4\ud2f0\ud2f0\uc758 \uc0c1\ud0dc \ubcc0\ud654\ub97c \uac10\uc9c0\ud569\ub2c8\ub2e4. \uc5d4\ud2f0\ud2f0\uc758 \ud544\ub4dc \uac12\uc774 \ubcc0\uacbd\ub418\uba74, \uc774 \ubcc0\uacbd \uc0ac\ud56d\uc740 \uc601\uc18d\uc131 \ucee8\ud14d\uc2a4\ud2b8\uc5d0 \uc758\ud574 \uc790\ub3d9\uc73c\ub85c \uac10\uc9c0\ub418\uc5b4, \ud2b8\ub79c\uc7ad\uc158\uc774 \ucee4\ubc0b\ub420 \ub54c \ud574\ub2f9 \ubcc0\uacbd \uc0ac\ud56d\uc774 \ub370\uc774\ud130\ubca0\uc774\uc2a4\uc5d0 \ubc18\uc601\ub429\ub2c8\ub2e4. \uc774 \ub54c\ubb38\uc5d0 \uac1c\ubc1c\uc790\ub294 \ub9e4\ubc88 \uba85\uc2dc\uc801\uc73c\ub85c \uc5c5\ub370\uc774\ud2b8 \ucffc\ub9ac\ub97c \uc791\uc131\ud560 \ud544\uc694\uac00 \uc5c6\uc2b5\ub2c8\ub2e4.<\/p>\n
\uc2a4\ud504\ub9c1 \ubd80\ud2b8\uc758 JPA\ub294 \uc4f0\uae30 \uc9c0\uc5f0 \uc804\ub7b5\uc744 \uc0ac\uc6a9\ud558\uc5ec \ud6a8\uc728\uc801\uc778 \ud2b8\ub79c\uc7ad\uc158 \uad00\ub9ac\ub97c \uc81c\uacf5\ud569\ub2c8\ub2e4. \uc989, \uc5d4\ud2f0\ud2f0\uac00 \ubcc0\uacbd\ub418\ub354\ub77c\ub3c4 \uc989\uc2dc \ub370\uc774\ud130\ubca0\uc774\uc2a4\uc5d0 \ubc18\uc601\ud558\uc9c0 \uc54a\uace0, \ud2b8\ub79c\uc7ad\uc158\uc774 \ucee4\ubc0b\ub420 \ub54c \ud55c \ubc88\uc5d0 \ubaa8\ub450 \uc801\uc6a9\ud569\ub2c8\ub2e4. \uc774\ub7ec\ud55c \ubc29\uc2dd\uc740 \ub370\uc774\ud130\ubca0\uc774\uc2a4\uc758 \ubd80\ud558\ub97c \uc904\uc774\uace0 \uc131\ub2a5\uc744 \ud5a5\uc0c1\uc2dc\ud0ac \uc218 \uc788\uc2b5\ub2c8\ub2e4.<\/p>\n
\uc2a4\ud504\ub9c1 \ubd80\ud2b8\ub97c \ud1b5\ud574 \uc601\uc18d\uc131 \ucee8\ud14d\uc2a4\ud2b8\ub97c \uc124\uc815\ud558\ub294 \uacfc\uc815\uc740 \ub9e4\uc6b0 \uac04\ub2e8\ud569\ub2c8\ub2e4. JPA \uc124\uc815\uc744 \ud1b5\ud574 \uc790\ub3d9\uc73c\ub85c EntityManagerFactory\uc640 \uc601\uc18d\uc131 \ucee8\ud14d\uc2a4\ud2b8\uac00 \uc0dd\uc131\ub429\ub2c8\ub2e4. \uc544\ub798\ub294 \uae30\ubcf8\uc801\uc778 \uc124\uc815 \uc608\uc2dc\uc785\ub2c8\ub2e4.<\/p>\n
application.properties\n spring.datasource.url=jdbc:mysql:\/\/localhost:3306\/mydb\n spring.datasource.username=myuser\n spring.datasource.password=mypassword\n spring.jpa.hibernate.ddl-auto=update\n <\/code><\/pre>\n4. \uc601\uc18d\uc131 \ucee8\ud14d\uc2a4\ud2b8\uc640 EntityManager<\/h2>\n
EntityManager\ub294 \uc601\uc18d\uc131 \ucee8\ud14d\uc2a4\ud2b8\uc758 \uc8fc\uc694 \uc778\ud130\ud398\uc774\uc2a4\ub85c, \ubaa8\ub4e0 \ub370\uc774\ud130\ubca0\uc774\uc2a4 \uc791\uc5c5\uc740 \uc774 \uac1d\uccb4\ub97c \ud1b5\ud574 \uc218\ud589\ub429\ub2c8\ub2e4. \uc2a4\ud504\ub9c1\uc5d0\uc11c\ub294 @PersistenceContext \uc8fc\uc11d\uc744 \ud1b5\ud574 EntityManager\ub97c \uc8fc\uc785\ubc1b\uc544 \uc0ac\uc6a9\ud560 \uc218 \uc788\uc2b5\ub2c8\ub2e4.<\/p>\n
import javax.persistence.EntityManager;\n import javax.persistence.PersistenceContext;\n\n @Service\n public class MyService {\n @PersistenceContext\n private EntityManager entityManager;\n\n public void save(MyEntity entity) {\n entityManager.persist(entity);\n }\n }\n <\/code><\/pre>\n5. \uc601\uc18d\uc131 \ucee8\ud14d\uc2a4\ud2b8\uc758 \ud65c\uc6a9 \uc608\uc2dc<\/h2>\n
\uc544\ub798\ub294 \uc601\uc18d\uc131 \ucee8\ud14d\uc2a4\ud2b8\uc758 \uae30\ubcf8\uc801\uc778 \ud65c\uc6a9 \uc608\uc2dc\ub97c \ubcf4\uc5ec\uc90d\ub2c8\ub2e4.<\/p>\n
5.1. \uc5d4\ud2f0\ud2f0 \uc0dd\uc131<\/h3>\npublic void createEntity() {\n MyEntity entity = new MyEntity();\n entity.setName(\"Sample Name\");\n \/\/ \uc601\uc18d\uc131 \ucee8\ud14d\uc2a4\ud2b8\uc5d0 \uc800\uc7a5\n entityManager.persist(entity);\n }\n <\/code><\/pre>\n5.2. \uc5d4\ud2f0\ud2f0 \uc218\uc815<\/h3>\npublic void updateEntity(Long id, String newName) {\n MyEntity entity = entityManager.find(MyEntity.class, id);\n entity.setName(newName); \n \/\/ \ubcc0\uacbd \uc0ac\ud56d\uc740 \uc790\ub3d9\uc73c\ub85c \ubc18\uc601\ub428\n }\n <\/code><\/pre>\n5.3. \uc5d4\ud2f0\ud2f0 \uc0ad\uc81c<\/h3>\npublic void deleteEntity(Long id) {\n MyEntity entity = entityManager.find(MyEntity.class, id);\n entityManager.remove(entity); \n }\n <\/code><\/pre>\n6. \uc601\uc18d\uc131 \ucee8\ud14d\uc2a4\ud2b8\uc758 \ubc94\uc704\uc640 \uc0dd\uba85\uc8fc\uae30<\/h2>\n
\uc601\uc18d\uc131 \ucee8\ud14d\uc2a4\ud2b8\ub294 \uc77c\ubc18\uc801\uc73c\ub85c \ud2b8\ub79c\uc7ad\uc158\uc758 \ubc94\uc704\uc5d0 \ub530\ub77c \uc0dd\uba85\uc8fc\uae30\uac00 \uacb0\uc815\ub429\ub2c8\ub2e4. \uae30\ubcf8\uc801\uc73c\ub85c \uc2a4\ud504\ub9c1\uc5d0\uc11c \uc120\uc5b8\uc801 \ud2b8\ub79c\uc7ad\uc158\uc744 \uc801\uc6a9\ud560 \uacbd\uc6b0, \ud2b8\ub79c\uc7ad\uc158\uc774 \uc2dc\uc791\ub418\ub294 \uc2dc\uc810\uc5d0 \uc601\uc18d\uc131 \ucee8\ud14d\uc2a4\ud2b8\uac00 \uc0dd\uc131\ub418\uace0 \ud2b8\ub79c\uc7ad\uc158\uc774 \uc885\ub8cc\ub418\uba74 \uc601\uc18d\uc131 \ucee8\ud14d\uc2a4\ud2b8\ub3c4 \uc885\ub8cc\ub429\ub2c8\ub2e4.<\/p>\n
7. \uc601\uc18d\uc131 \ucee8\ud14d\uc2a4\ud2b8\uc758 \uc131\ub2a5 \ucd5c\uc801\ud654<\/h2>\n
\uc601\uc18d\uc131 \ucee8\ud14d\uc2a4\ud2b8\ub97c \ud65c\uc6a9\ud558\ub354\ub77c\ub3c4 \uc131\ub2a5 \uc774\uc288\uac00 \ubc1c\uc0dd\ud560 \uc218 \uc788\uc2b5\ub2c8\ub2e4. \ub2e4\uc74c\uc740 \uc131\ub2a5\uc744 \ucd5c\uc801\ud654\ud558\ub294 \uba87 \uac00\uc9c0 \ubc29\ubc95\uc785\ub2c8\ub2e4.<\/p>\n
\n- FetchType \uc124\uc815<\/strong>: \uc9c0\uc5f0 \ub85c\ub529(LAZY)\uacfc \uc989\uc2dc \ub85c\ub529(EAGER) \uc124\uc815\uc744 \ud1b5\ud574 \ud544\uc694\uc5d0 \ub530\ub77c \ub370\uc774\ud130\ub97c \ub85c\ub4dc\ud574\uc57c \ud569\ub2c8\ub2e4.<\/li>\n
- Batch \ucc98\ub9ac<\/strong>: \uc5ec\ub7ec \uac1c\uc758 \uc5d4\ud2f0\ud2f0\ub97c \ud55c \ubc88\uc5d0 \uc800\uc7a5\ud558\uac70\ub098 \uc0ad\uc81c\ud560 \ub54c\ub294 \ubc30\uce58 \ucc98\ub9ac\ub97c \ud1b5\ud574 \uc131\ub2a5\uc744 \uac1c\uc120\ud560 \uc218 \uc788\uc2b5\ub2c8\ub2e4.<\/li>\n
- \uc815\uc801 \ucffc\ub9ac \uc0ac\uc6a9<\/strong>: \ubcf5\uc7a1\ud55c \ucffc\ub9ac\uc758 \uacbd\uc6b0 JPA\uc758 Criteria API\ub098 JPQL\uc744 \ud65c\uc6a9\ud558\uae30\ubcf4\ub2e4\ub294 \ub124\uc774\ud2f0\ube0c \ucffc\ub9ac\ub97c \uc0ac\uc6a9\ud558\ub294 \uac83\uc774 \uc720\ub9ac\ud560 \uc218 \uc788\uc2b5\ub2c8\ub2e4.<\/li>\n<\/ul>\n
8. \uacb0\ub860<\/h2>\n
\uc601\uc18d\uc131 \ucee8\ud14d\uc2a4\ud2b8\ub294 \uc2a4\ud504\ub9c1 \ubd80\ud2b8\uc640 JPA\ub97c \ud65c\uc6a9\ud55c \ubc31\uc5d4\ub4dc \uac1c\ubc1c\uc5d0 \uc788\uc5b4 \ub9e4\uc6b0 \uc911\uc694\ud55c \uac1c\ub150\uc785\ub2c8\ub2e4. \uc774\ub97c \ud1b5\ud574 \ub370\uc774\ud130\ubca0\uc774\uc2a4\uc640\uc758 \uc6d0\ud65c\ud55c \uc0c1\ud638\uc791\uc6a9 \ubc0f \uc131\ub2a5 \ucd5c\uc801\ud654\uac00 \uac00\ub2a5\ud574\uc9d1\ub2c8\ub2e4. \uc774\ubc88 \uac15\uc88c\uc5d0\uc11c\ub294 \uc601\uc18d\uc131 \ucee8\ud14d\uc2a4\ud2b8\uc758 \uae30\ubcf8 \uac1c\ub150, \uc0ac\uc6a9\ubc95, \uadf8\ub9ac\uace0 \uc131\ub2a5 \ucd5c\uc801\ud654 \ubc29\ubc95\uae4c\uc9c0 \ud3ec\uad04\uc801\uc73c\ub85c \ub2e4\ub8e8\uc5b4 \ubcf4\uc558\uc2b5\ub2c8\ub2e4. \uc55e\uc73c\ub85c\ub3c4 \uc2a4\ud504\ub9c1 \ubd80\ud2b8\uc640 JPA\ub97c \ud1b5\ud574 \ubcf4\ub2e4 \ub098\uc740 \uc560\ud50c\ub9ac\ucf00\uc774\uc158\uc744 \uac1c\ubc1c\ud574 \ub098\uac00\uc2dc\uae38 \ubc14\ub78d\ub2c8\ub2e4.<\/p>\n