Invalid column index , update using PreparedStatement

Question

I am updating table using PreparedStatement

the following code works perfectly

pst = conn.prepareStatement("UPDATE playjdbc SET jlname ='javafx10new' WHERE jfname = 'java10'");
int i = pst.executeUpdate();

but when i tried like this it throwing exception

 pst = conn.prepareStatement("UPDATE playjdbc SET jlname ='javafx10new' WHERE jfname =?");
 pst.setString(2, "java10"); // yeah second column is jfname

 int i = pst.executeUpdate();

stacktrace :

java.sql.SQLException: Invalid column index
    at oracle.jdbc.driver.OraclePreparedStatement.setStringInternal(OraclePreparedStatement.java:5330)
    at oracle.jdbc.driver.OraclePreparedStatement.setString(OraclePreparedStatement.java:5318)
    at oracle.jdbc.driver.OraclePreparedStatementWrapper.setString(OraclePreparedStatementWrapper.java:282)
    at com.indus.database.EmployeeDTO.updateData(EmployeeDTO.java:114)

Solution 1

2 in following refers to the position of the question mark in query string, not to the position of column in database table and not to the order of column names used in query:

 pst.setString(2, "java10"); // yeah second column is jfname

Use 1 instead.

pst.setString(1, "java10"); // first question mark is jfname

Solution 2

Please go through the setString() method specs:

http://docs.oracle.com/javase/1.4.2/docs/api/java/sql/PreparedStatement.html#setString%28int,%20java.lang.String%29

The correct approach is :

pst = conn.prepareStatement("UPDATE playjdbc SET jlname ='javafx10new' WHERE jfname =?");
pst.setString(1, "java10"); 

int i = pst.executeUpdate();