Problem with ResultSet in a loop

Question

hi,
i have a probleme with ResultSet when, my code is bellow
ResultSet rs = stmt.executeQuery(sql);
sql="SELECT NAME FROM prestationtemp";
rs = stmt.executeQuery(sql);
String sqlDel="";
while (rs.next())
sqlDel="Delete from prestation where NAME="+rs.getString("NAME");
stmt.executeQuery(sqlDel);
the problem is that the loop iterate just once like if there is just one record, and if I remove stmt.executeQuery(sqlDel); from the loop it iterate normaly.
thanks in advance.

Answer 1

you will need to use 2 Statments e.g.
Statement stmt1 = connection.createStatement();
Statement stmt2 = connection.createStatement();
ResultSet rs = stmt.executeQuery(sql);
sql="SELECT NAME FROM prestationtemp";
rs = stmt1.executeQuery(sql);
String sqlDel="";
while (rs.next())
sqlDel="Delete from prestation where NAME="+rs.getString("NAME");
stmt2.executeQuery(sqlDel);
} When you reuse a Statement, any resultsets previously created are automatically closed.
Looking at your code, it seems that you only need 1 SQL call:
Delete from prestation where NAME in (SELECT NAME FROM prestationtemp)
Much more efficient!