Question

I want to batch up multiple types of database calls in one PreparedStatement. Is this possible?

Is there anyway to do something like

PreparedStatement pstmt = connection.prepareStatement("?");

where the ? can either be INSERT INTO MY_TABLE VALUES(1,2,3,4) or it could be UPDATE MY_TABLE, SET MY_VAL='1' WHERE MY_VAL IS NULL

Or do I always need to specify a table and action for my prepared statement?

Answer 1

Java will not allow you add only ? in preparedstatement string parameter, as it expects the ? for the place holder only for the parameters to the give SQL.

For your case, you may have to have 2 prepared statement objects, and in loop through, you can make a decision which one to call. So it would be something like below:

PreparedStatement insertPstmt = connection.prepareStatement("INSERT INTO MY_TABLE VALUES(?,?,?,?)");
PreparedStatement updatePstmt = connection.prepareStatement("UPDATE MY_TABLE, SET MY_VAL=? WHERE MY_VAL IS NULL");

While (<condition>) {
  If (<insert condition>) {
    // use insert pstmt and add batch
  } else {
    // use update pstmt and add batch
  }
}

insertPstmt.executeBatch(); 
updatePstmt.executeBatch();

if you have any insert , which has dependency on the update, you might execute the batches accordingly. This will make sure that the update will work correctly. I would think of executing insert first, as they might not depend on update.