EN
Spring Boot 2 - JdbcTemplate throws: java.sql.SQLException: Before start of result set
1
answers
4
points
I have trouble uring JdbcTemplate query() function getting single result from ResultSet.
This is exception I got:
java.sql.SQLException: Before start of result set
This is stack trace:
java.sql.SQLException: Before start of result set
at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:129) ~[mysql-connector-java-8.0.22.jar:8.0.22]
at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:97) ~[mysql-connector-java-8.0.22.jar:8.0.22]
at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:89) ~[mysql-connector-java-8.0.22.jar:8.0.22]
at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:63) ~[mysql-connector-java-8.0.22.jar:8.0.22]
at com.mysql.cj.jdbc.result.ResultSetImpl.checkRowPos(ResultSetImpl.java:492) ~[mysql-connector-java-8.0.22.jar:8.0.22]
at com.mysql.cj.jdbc.result.ResultSetImpl.getObject(ResultSetImpl.java:1299) ~[mysql-connector-java-8.0.22.jar:8.0.22]
at com.mysql.cj.jdbc.result.ResultSetImpl.getLong(ResultSetImpl.java:823) ~[mysql-connector-java-8.0.22.jar:8.0.22]
at com.zaxxer.hikari.pool.HikariProxyResultSet.getLong(HikariProxyResultSet.java) ~[HikariCP-4.0.3.jar:?]
at chat.MessagesService.lambda$fetchMessages$1(MessagesService.java:215) ~[classes/:?]
at org.springframework.jdbc.core.JdbcTemplate$1QueryStatementCallback.doInStatement(JdbcTemplate.java:453) ~[spring-jdbc-5.3.13.jar:5.3.13]
at org.springframework.jdbc.core.JdbcTemplate.execute(JdbcTemplate.java:381) ~[spring-jdbc-5.3.13.jar:5.3.13]
at org.springframework.jdbc.core.JdbcTemplate.query(JdbcTemplate.java:465) ~[spring-jdbc-5.3.13.jar:5.3.13]
...
SQL query I used:
SELECT COUNT(*)
FROM `messages` m
WHERE (m.`removal_time` IS NULL)
My java source code:
// import org.springframework.jdbc.core.JdbcTemplate;
// @Autowire
// private JdbcTemplate jdbcTemplate;
public Long getCount() {
String sqlQuery = "SELECT COUNT(*) \n" +
"FROM `messages` m \n" +
"WHERE (m.`removal_time` IS NULL)\n";
return this.jdbcTemplate.query(sqlQuery, (resultSet) -> (Long) resultSet.getLong(1));
}
1 answer
5
points
In the above case you need to call resultSet.next() function before calling resultSet.getLong(1) function.
Fixed source code:
public Long getCount() {
String sqlQuery = "SELECT COUNT(*) \n" +
"FROM `messages` m \n" +
"WHERE (m.`removal_time` IS NULL)\n";
long rowsCount = this.jdbcTemplate.query(sqlQuery, (resultSet) -> {
if (resultSet.next()) {
return resultSet.getLong(1);
}
return 0L;
});
return rowsCount;
}
0 comments
Add comment