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javamysqlprepared-statementauto-increment

Is there a way to retrieve the autoincrement ID from a prepared statement


Is there a way to retrieve the auto generated key from a DB query when using a java query with prepared statements.

For example, I know AutoGeneratedKeys can work as follows.

stmt = conn.createStatement();

stmt.executeUpdate(sql, Statement.RETURN_GENERATED_KEYS);
if(returnLastInsertId) {
    ResultSet rs = stmt.getGeneratedKeys();
    rs.next();
    auto_id = rs.getInt(1);
} 

However. What if I want to do an insert with a prepared Statement.

String sql = "INSERT INTO table (column1, column2) values(?, ?)";
stmt = conn.prepareStatement(sql);

//this is an error
stmt.executeUpdate(Statement.RETURN_GENERATED_KEYS);
if(returnLastInsertId) {
    //this is an error since the above is an error
    ResultSet rs = stmt.getGeneratedKeys();
    rs.next();
    auto_id = rs.getInt(1);
} 

Is there a way to do this that I don't know about. It seems from the javadoc that PreparedStatements can't return the Auto Generated ID.


Solution

  • Yes. See here. Section 7.1.9. Change your code to:

    String sql = "INSERT INTO table (column1, column2) values(?, ?)";
    stmt = conn.prepareStatement(sql, Statement.RETURN_GENERATED_KEYS);
    
    
    stmt.executeUpdate();
    if(returnLastInsertId) {
       ResultSet rs = stmt.getGeneratedKeys();
        rs.next();
       auto_id = rs.getInt(1);
    }