Spring Data JPA是个非常强大的ORM持久化解决方案，免去了mybatis或spring jdbcTemplate的开发人员编写脚本的无趣工作。
通过简单明了地约定好接口方法的规则，来自动生成相应的JPQL语句，映射成PO对象，能大幅节省开发人员的编码量。
接口方法的命名规则也很简单，明白And、Or、Is、Equal、Greater、StartingWith等英文单词的含义，就可以写接口方法了。
以下是从Spring Data JPA官方网站上的docs整理而来，网上其他有些文章写的有的是错的，
大于等于、小于等于应为：GreaterThanEqual、LessThanEqual，而不是GreaterThanEquals、LessThanEquals，如果带了s，会导致程序启动报错。
| 关键词 | SQL符号 | 样例 | 对应JPQL 语句片段 |
| And | and | findByLastnameAndFirstname | … where x.lastname = ?1 and x.firstname = ?2 |
| Or | or | findByLastnameOrFirstname | … where x.lastname = ?1 or x.firstname = ?2 |
| Is,Equals | = | findByFirstname,findByFirstnameIs,findByFirstnameEquals | … where x.firstname = ?1 |
| Between | between xxx and xxx | findByStartDateBetween | … where x.startDate between ?1 and ?2 |
| LessThan | < | findByAgeLessThan | … where x.age < ?1 |
| LessThanEqual | <= | findByAgeLessThanEqual | … where x.age <= ?1 |
| GreaterThan | > | findByAgeGreaterThan | … where x.age > ?1 |
| GreaterThanEqual | >= | findByAgeGreaterThanEqual | … where x.age >= ?1 |
| After | > | findByStartDateAfter | … where x.startDate > ?1 |
| Before | < | findByStartDateBefore | … where x.startDate < ?1 |
| IsNull | is null | findByAgeIsNull | … where x.age is null |
| IsNotNull,NotNull | is not null | findByAge(Is)NotNull | … where x.age not null |
| Like | like | findByFirstnameLike | … where x.firstname like ?1 |
| NotLike | not like | findByFirstnameNotLike | … where x.firstname not like ?1 |
| StartingWith | like 'xxx%' | findByFirstnameStartingWith | … where x.firstname like ?1(parameter bound with appended %) |
| EndingWith | like 'xxx%' | findByFirstnameEndingWith | … where x.firstname like ?1(parameter bound with prepended %) |
| Containing | like '%xxx%' | findByFirstnameContaining | … where x.firstname like ?1(parameter bound wrapped in %) |
| OrderBy | order by | findByAgeOrderByLastnameDesc | … where x.age = ?1 order by x.lastname desc |
| Not | <> | findByLastnameNot | … where x.lastname <> ?1 |
| In | in() | findByAgeIn(Collection<Age> ages) | … where x.age in ?1 |
| NotIn | not in() | findByAgeNotIn(Collection<Age> ages) | … where x.age not in ?1 |
| TRUE | =true | findByActiveTrue() | … where x.active = true |
| FALSE | =false | findByActiveFalse() | … where x.active = false |
| IgnoreCase | upper(xxx)=upper(yyyy) | findByFirstnameIgnoreCase | … where UPPER(x.firstame) = UPPER(?1) |
Spring Data JPA官方文档
https://docs.spring.io/spring-data/jpa/docs/2.0.9.RELEASE/reference/html/