JDBCTemplate queryForMap for retrieving multiple rows [duplicate]

Question

Can I use queryForMap if there are multiple rows returned by the query.

For a single row, the below code works fine.

public Map<String, Object> retrieveMultipleRowsColumns(String deptName){
    return jdbcTemplate.queryForMap("SELECT DEPT_ID,DEPT_NAME FROM DEPT WHERE DEPT_NAME = ?", deptName);
}

How to modify this for multiple rows?

Answer 1

I know this is really old, but there is a much simpler way to do this if you're looking for a map.

Simply implement the ResultSetExtractor interface to define what type you want to return. Below is an example of how to use this. You'll be mapping it manually, but for a simple map, it should be straightforward.

jdbcTemplate.query("select string1,string2 from table where x=1", new ResultSetExtractor<Map>(){
    @Override
    public Map extractData(ResultSet rs) throws SQLException,DataAccessException {
        HashMap<String,String> mapRet= new HashMap<String,String>();
        while(rs.next()){
            mapRet.put(rs.getString("string1"),rs.getString("string2"));
        }
        return mapRet;
    }
});

This will give you a return type of Map that has multiple rows (however many your query returned) and not a list of Maps. You can view the ResultSetExtractor docs here: http://docs.spring.io/spring/docs/current/javadoc-api/org/springframework/jdbc/core/ResultSetExtractor.html