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It's the contribution of my younger martial brother again. I really like technology. The following is the original:
Today, when I read the official documents of Spring Data JPA, I found that there is no complete semantic translation of Jpa keywords. So I wrote a Chinese document today. If there is any mistake, I hope you can spray it lightly.
Here is the official picture with sample code and comments:
First, create the specified database by referring to the official documents
CREATE TABLE `demo_jpa` ( `id` int(11) NOT NULL AUTO_INCREMENT, `first_name` varchar(255) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL, `last_name` varchar(32) CHARACTER SET utf8 COLLATE utf8_general_ci NOT NULL, `sex` varchar(32) CHARACTER SET utf8 COLLATE utf8_general_ci NOT NULL, `email` varchar(32) CHARACTER SET utf8 COLLATE utf8_general_ci NOT NULL, `age` int(12) NOT NULL, PRIMARY KEY (`id`) USING BTREE ) ENGINE = InnoDB AUTO_INCREMENT = 6 CHARACTER SET = utf8 COLLATE = utf8_general_ci ROW_FORMAT = Dynamic;
Example code and notes < refer to the above order >
/** * @Author: EvilSay * @Date: 2019/2/25 16:15 */ public interface DemoJpaRepositories extends JpaRepository<DemoJpa,Integer> { //Find by firstName and LastName (both must be in the database) DemoJpa findByFirstNameAndLastName(String firstName, String lastName); //Find by firstName or LastName (one of them is OK) DemoJpa findByLastNameOrFirstName(String lastName,String firstName); //Find whether it exists in the database according to firstName < similar to the following keywords > //DemoJpa findByFirstName(String firstName); DemoJpa findByFirstNameIs(String firstName); //Data between age and age2 List<DemoJpa> findByAgeBetween(Integer age, Integer age2); //Data less than the specified age value List<DemoJpa> findByAgeLessThan(Integer age); //Data less than or equal to the specified age value List<DemoJpa> findByAgeLessThanEqual(Integer age); //Data greater than the specified age value List<DemoJpa> findByAgeGreaterThan(Integer age); //Data greater than or equal to the specified age value List<DemoJpa> findByAgeGreaterThanEqual(Integer age); //The data before the age value is specified is similar to the keyword < lessthan > List<DemoJpa> findByAgeAfter(Integer age); //The data after the specified age value is similar to the keyword < greaterthan > List<DemoJpa> findByAgeBefore(Integer age); //Return data with empty age field List<DemoJpa> findByAgeIsNull(); //Return data whose age field is not empty List<DemoJpa> findByAgeNotNull(); /** * At one time, I thought it was a fuzzy query similar to database, * But I went to the official document and saw that there were no wildcards in it. * So I think it's similar * DemoJpa findByFirstName(String firstName); * @see https://docs.spring.io/spring-data/jpa/docs/2.1.5.RELEASE/reference/html/#jpa.repositories */ DemoJpa findByFirstNameLike(String firstName); //Ditto List<DemoJpa> findByFirstNameNotLike(String firstName); //Find similar names in the database (for example, entering a name "M" Jpa will return mu lt iple data sources with names beginning with M) < similar database fuzzy query > List<DemoJpa> findByFirstNameStartingWith(String firstName); //Different name specified in lookup database (same as above) List<DemoJpa> findByFirstNameEndingWith(String firstName); //Find the specified data source contained (this is different from the above two fields in that it must input complete data to query) List<DemoJpa> findByFirstNameContaining(String firstName); //Select all data sources according to age and sort them in ascending order according to LastName List<DemoJpa> findByAgeOrderByLastName(Integer age); //Returns all data that is not the specified age List<DemoJpa> findByAgeNot(Integer age); //Finds data returned by multiple specified age s List<DemoJpa> findByAgeIn(List<Integer> age); }
Unit test < all passed >
@SpringBootTest @RunWith(SpringRunner.class) @Slf4j public class DemoJpaRepositoriesTest { @Autowired private DemoJpaRepositories repositories; @Test public void findByFirstNameAndLastName() { DemoJpa demoJpa = repositories.findByFirstNameAndLastName("May", "Eden"); Assert.assertEquals(demoJpa.getFirstName(),"May"); } @Test public void findByLastNameOrFirstName() { DemoJpa demoJpa = repositories.findByLastNameOrFirstName("Geordie", "Eden"); Assert.assertNotEquals(demoJpa.getLastName(),"Eden"); } @Test public void findByFirstNameIs() { DemoJpa demoJpa = repositories.findByFirstNameIs("amy"); Assert.assertNull(demoJpa); } @Test public void findByAgeBetween() { List<DemoJpa> demoJpaList = repositories.findByAgeBetween(15, 17); Assert.assertEquals(3,demoJpaList.size()); } @Test public void findByAgeLessThan() { List<DemoJpa> demoJpaList = repositories.findByAgeLessThan(17); Assert.assertEquals(2,demoJpaList.size()); } @Test public void findByAgeLessThanEqual() { List<DemoJpa> demoJpaList = repositories.findByAgeLessThanEqual(17); Assert.assertEquals(3,demoJpaList.size()); } @Test public void findByAgeGreaterThan() { List<DemoJpa> demoJpaList = repositories.findByAgeGreaterThan(17); Assert.assertEquals(2,demoJpaList.size()); } @Test public void findByAgeGreaterThanEqual() { List<DemoJpa> demoJpaList = repositories.findByAgeGreaterThanEqual(17); Assert.assertEquals(3,demoJpaList.size()); } @Test public void findByAgeAfter() { List<DemoJpa> demoJpaList = repositories.findByAgeAfter(17); Assert.assertEquals(2,demoJpaList.size()); } @Test public void findByAgeBefore() { List<DemoJpa> demoJpaList = repositories.findByAgeBefore(17); Assert.assertEquals(2,demoJpaList.size()); } @Test public void findByAgeIsNull() { List<DemoJpa> demoJpaList = repositories.findByAgeIsNull(); Assert.assertEquals(0,demoJpaList.size()); } @Test public void findByAgeNotNull() { List<DemoJpa> demoJpaList = repositories.findByAgeNotNull(); Assert.assertEquals(5,demoJpaList.size()); } @Test public void findByFirstNameLike() { DemoJpa demoJpa = repositories.findByFirstNameLike("May"); Assert.assertNotNull(demoJpa); } @Test public void findByFirstNameNotLike() { } @Test public void findByFirstNameStartingWith() { List<DemoJpa> demoJpaList = repositories.findByFirstNameStartingWith("May"); Assert.assertEquals(2,demoJpaList.size()); } @Test public void findByFirstNameEndingWith() { List<DemoJpa> demoJpaList = repositories.findByFirstNameEndingWith("Evil"); Assert.assertEquals(0,demoJpaList.size()); } @Test public void findByFirstNameContaining() { List<DemoJpa> demoJpaList = repositories.findByFirstNameContaining("hack"); Assert.assertEquals(0,demoJpaList.size()); } @Test public void findByAgeOrderByLastName() { List<DemoJpa> demoJpaList = repositories.findByAgeOrderByLastName(18); for (DemoJpa demoJpaL : demoJpaList){ log.info("Data results"+demoJpaL.toString()); } } @Test public void findByAgeNot() { List<DemoJpa> demoJpaList = repositories.findByAgeNot(20); Assert.assertEquals(5,demoJpaList.size()); } @Test public void findByAgeIn() { List<DemoJpa> demoJpaList = repositories.findByAgeIn(Arrays.asList(15, 16)); Assert.assertEquals(2,demoJpaList.size()); } }Posterior language
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