Mysql error when select like - mysql

Question

pls help to solve below mentioned error :
com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'r.Username LIKE '%usernameanswer%' and r.Createtime > NOW() - INTERVAL 30 SECOND
Code
public List <CorrekctanswerModel> answerlist(String usernameanswer) throws Exception {
log.info("daomimpl" + usernameanswer);
List<CorrekctanswerModel> answerarray = new ArrayList<CorrekctanswerModel>();
Connection c = null;
PreparedStatement ps = null;
ResultSet rs = null;
String sql = " select s.NAME as Subject, d.value as variant, r.Username, r.UserAnswer, r.Correctanswer, r.Createtime from resultlog r " +
" inner join test_table t on t.ID = r.QuestionId " +
" inner join subject s on s.ID= t.SUBJECT " +
" inner join dictionary d on d.ID = t.Variant" +
"where r.Username LIKE '%usernameanswer%' and r.Createtime > NOW() - INTERVAL 30 SECOND " ;
try {
c = DbHelper.getConnection();
if (c != null) {
ps = c.prepareStatement(sql);
rs = ps.executeQuery();
while (rs.next()) {
CorrekctanswerModel rep = new CorrekctanswerModel();
rep.setSubject(rs.getString("Subject"));
rep.setVariant(rs.getString("variant"));
rep.setUsername(rs.getString("Username"));
rep.setUseranswer(rs.getString("UserAnswer"));
rep.setCorrekctanswer(rs.getString("Correctanswer"));
rep.setCreatedate(rs.getDate("Createtime"));
answerarray.add(rep);
}
}
} catch (Exception ex) {
ex.printStackTrace();
} finally {
JdbcUtility.close(c, ps, rs);
}
return answerarray;
}

Answer 1

I'm going to add this as an answer in case someone stumbles upon this question...
In your code, SQL is generated with these lines:
String sql = " select <fields> from resultlog r " +
" inner join test_table t on t.ID = r.QuestionId " +
" inner join subject s on s.ID= t.SUBJECT " +
" inner join dictionary d on d.ID = t.Variant" +
"where r.Username LIKE '%usernameanswer%' and ... " ;
There should be a white space before where OR a white space after t.Variant. In its current form, the query will do this:
... inner join dictionary d on d.ID = t.Variantwhere r.Username ...
Adding a space before where like so:
String sql = " select <fields> from resultlog r " +
" inner join test_table t on t.ID = r.QuestionId " +
" inner join subject s on s.ID= t.SUBJECT " +
" inner join dictionary d on d.ID = t.Variant" +
" where r.Username LIKE '%usernameanswer%' and ... " ;
will result in your query written like this:
... inner join dictionary d on d.ID = t.Variant where r.Username ...
Also, it looks like usernameanswer is a variable. If it is, the where clause will look like this:
" where r.Username LIKE '%" + usernameanswer + "%' and ... " ;