I'm trying to learn how to work with a database in Java using MySql. I'm having this error:
com.mysql.jdbc.MysqlDataTruncation: Data truncation: Truncated incorrect DOUBLE value: 'q'
which means I'm having type mismatch but I can't figure out why. Here is my code. I have included ResultSetMetaData to show the datatypes of columns.
import java.sql.*;
public class Prep {
public static void main(String[] args) throws SQLException {
try {
Connection c=DriverManager.getConnection(host, username, password);
PreparedStatement pstmt=c.prepareStatement("update emp2211 set name=? where id=?");
ResultSet rs = pstmt.executeQuery("Select * from emp2211");
ResultSetMetaData rsmd= rs.getMetaData();
System.out.println("Total columns: "+rsmd.getColumnCount());
System.out.println("Column Name of 1st column: "+rsmd.getColumnName(1));
System.out.println("Column Type Name of 1st column: "+rsmd.getColumnTypeName(1));
System.out.println("Column Name of 2nd column: "+rsmd.getColumnName(2));
System.out.println("Column Type Name of 2nd column: "+rsmd.getColumnTypeName(2));
pstmt.setInt(1, 800);
pstmt.setString(2, "q");
pstmt.executeUpdate();
while(rs.next()){
System.out.println(rs.getString(1));
System.out.println(rs.getString(2));
}
pstmt.close();
c.close();
} catch (Exception e) {
System.out.println(e);
}
}
}
This is my output
Total columns: 2
Column Name of 1st column: id
Column Type Name of 1st column: INT
Column Name of 2nd column: name
Column Type Name of 2nd column: VARCHAR
com.mysql.jdbc.MysqlDataTruncation: Data truncation: Truncated incorrect DOUBLE value: 'q'
You are setting a String
to an numeric column.
PreparedStatement pstmt=c.prepareStatement("update emp2211 set name=? where id=?");
...
pstmt.setInt(1, 800);
pstmt.setString(2, "q"); // the second ? is referred to id
Probably you need to the following?
PreparedStatement pstmt=c.prepareStatement("update emp2211 set name=? where id=?");
...
pstmt.setString(1, "q");
pstmt.setInt(2, 800);