Jdbctemplate query for string: EmptyResultDataAccessException: Incorrect result size: expected 1, actual 0

Question

I am using Jdbctemplate to retrieve a single String value from the db. Here is my method.

    public String test() {
        String cert=null;
        Strin         


        

Answer 1

I just catch this "EmptyResultDataAccessException"

public Myclass findOne(String id){
    try {
        Myclass m = this.jdbcTemplate.queryForObject(
                "SELECT * FROM tb_t WHERE id = ?",
                new Object[]{id},
                new RowMapper() {
                    public Myclass mapRow(ResultSet rs, int rowNum) throws SQLException {
                        Myclass m = new Myclass();
                        m.setName(rs.getString("name"));
                        return m;
                    }
                });
        return m;
    } catch (EmptyResultDataAccessException e) { // result.size() == 0;
        return null;
    }
}

then you can check:

if(m == null){
    // insert operation.
}else{
    // update operation.
}