I use Spring-Data-JDBC (not JPA) and want to set the fetch-size.
I know that the the classic org.springframwork.jdbc.core.JdbcTemplate has a setFetchSize(int) method, but I have Spring-Data-JDBC repository:
org.springframework.data.repository.Repository;
org.springframework.data.jdbc.repository.query.Query;
/** This is a Spring Data <b>JDBC</b> (JDBC not JPA!). */
public interface UserDao extends Repository<User, Long> {
@Query(value = UserRowMapper.SELECT_BY_NAME_STATEMENT
rowMapperClass = UserRowMapper.class)
Optional<User> findByName(String name);
}
and this is the relevant part of the configuration:
@Configuration
@EnableJdbcRepositories
public class AppConfigSpringDataJdbc extends AbstractJdbcConfiguration {
@Autowired
private DataSource dataSource;
@Bean
public NamedParameterJdbcTemplate namedParameterJdbcTemplate() {
return new NamedParameterJdbcTemplate(this.dataSource);
}
}
So my question is: How/Where to set the sql query fetch-size when using Spring-Data-JDBC, either by query or in general?
(The common solutions for Spring-Data-JPA will not work, because there is no persistence.xml or javax.persistence.QueryHintannotation because it is JDBC)
You can create NamedParameterJdbcTemplate using custom JdbcTemplate.
@Bean
JdbcOperations jdbcOperations(DataSource dataSource) {
final var jdbcTemplate = new JdbcTemplate(dataSource);
jdbcTemplate.setFetchSize(100);
return jdbcTemplate;
}
@Bean
NamedParameterJdbcOperations namedParameterJdbcOperations(JdbcOperations operations) {
return new NamedParameterJdbcTemplate(operations);
}