有没有使用PostgreSQL JSON / hstore与JdbcTemplate
的方法吗? ESP查询支持。
对于例如:
hstore:
INSERT INTO hstore_test (data) VALUES ('"key1"=>"value1", "key2"=>"value2", "key3"=>"value3"')
SELECT data -> 'key4' FROM hstore_test
SELECT item_id, (each(data)).* FROM hstore_test WHERE item_id = 2
对JSON
insert into jtest (data) values ('{"k1": 1, "k2": "two"}');
select * from jtest where data ->> 'k2' = 'two';
虽然已经很晚了一个答案(用于插入的部分),我希望它可能是别人有用的人:
就拿一个HashMap的键/值对:
Map<String, String> hstoreMap = new HashMap<>();
hstoreMap.put("key1", "value1");
hstoreMap.put("key2", "value2");
PGobject jsonbObj = new PGobject();
jsonbObj.setType("json");
jsonbObj.setValue("{\"key\" : \"value\"}");
使用以下方式将它们插入到PostgreSQL之一:
1)
jdbcTemplate.update(conn -> {
PreparedStatement ps = conn.prepareStatement( "INSERT INTO table (hstore_col, jsonb_col) VALUES (?, ?)" );
ps.setObject( 1, hstoreMap );
ps.setObject( 2, jsonbObj );
});
2)
jdbcTemplate.update("INSERT INTO table (hstore_col, jsonb_col) VALUES(?,?)",
new Object[]{ hstoreMap, jsonbObj }, new int[]{Types.OTHER, Types.OTHER});
3)设置hstoreMap / jsonbObj型地图的POJO(hstoreCol和jsonbObjCol是类型pgobject的的)
BeanPropertySqlParameterSource sqlParameterSource = new BeanPropertySqlParameterSource( POJO );
sqlParameterSource.registerSqlType( "hstore_col", Types.OTHER );
sqlParameterSource.registerSqlType( "jsonb_col", Types.OTHER );
namedJdbcTemplate.update( "INSERT INTO table (hstore_col, jsonb_col) VALUES (:hstoreCol, :jsonbObjCol)", sqlParameterSource );
而要获得的价值:
(Map<String, String>) rs.getObject( "hstore_col" ));
((PGobject) rs.getObject("jsonb_col")).getValue();
甚至比JdbcTemplate
容易,你可以使用hibernate-types
开源项目坚持HStore性能。
首先,你需要Maven的依赖关系:
<dependency>
<groupId>com.vladmihalcea</groupId>
<artifactId>hibernate-types-52</artifactId>
<version>${hibernate-types.version}</version>
</dependency>
然后,假设您有以下Book
实体:
@Entity(name = "Book")
@Table(name = "book")
@TypeDef(name = "hstore", typeClass = PostgreSQLHStoreType.class)
public static class Book {
@Id
@GeneratedValue
private Long id;
@NaturalId
@Column(length = 15)
private String isbn;
@Type(type = "hstore")
@Column(columnDefinition = "hstore")
private Map<String, String> properties = new HashMap<>();
//Getters and setters omitted for brevity
}
请注意,我们标注了该properties
注释的@Type
实体属性,我们指定先前通过hstore
定义为使用@TypeDef
定制Hibernate类型的PostgreSQLHStoreType
类型。
现在,存储以下Book
实体时:
Book book = new Book();
book.setIsbn("978-9730228236");
book.getProperties().put("title", "High-Performance Java Persistence");
book.getProperties().put("author", "Vlad Mihalcea");
book.getProperties().put("publisher", "Amazon");
book.getProperties().put("price", "$44.95");
entityManager.persist(book);
Hibernate的执行下面的SQL INSERT语句:
INSERT INTO book (isbn, properties, id)
VALUES (
'978-9730228236',
'"author"=>"Vlad Mihalcea",
"price"=>"$44.95", "publisher"=>"Amazon",
"title"=>"High-Performance Java Persistence"',
1
)
而且,当我们获取Book
实体,我们可以看到,所有的属性都正确获取:
Book book = entityManager
.unwrap(Session.class)
.bySimpleNaturalId(Book.class)
.load("978-9730228236");
assertEquals(
"High-Performance Java Persistence",
book.getProperties().get("title")
);
assertEquals(
"Vlad Mihalcea",
book.getProperties().get("author")
);
有关详细信息,请this article。