Tables with Primary Key Column "GENERATED ... AS IDENTITY"

This section describes how to create a table primary key column defined as 'GENERATED ... AS IDENTITY'.

Similar to Microsoft SQL Server, Derby supports IDENTITY columns to help you creating auto-incremented sequence values for primary key columns. Derby offers two variations of IDENTITY columns:

In order to try IDENTITY columns and provide a test table for testing DML (Data Manipulation Statements), I wrote the following program to create a table called "Profile" with the primary key column defined as an IDENTITY column:

/* DerbyIdentityColumn.java
 - Copyright (c) 2015, HerongYang.com, All Rights Reserved.
 */
import java.sql.*;
public class DerbyIdentityColumn {
  public static void main(String [] args) {
    Connection con = null;
    try {
      con = DriverManager.getConnection(
        "jdbc:derby://localhost/TestDB");

// Creating a database table
      Statement sta = con.createStatement(); 
      int count = sta.executeUpdate(
        "CREATE TABLE Profile ("
        + " ID INTEGER PRIMARY KEY GENERATED ALWAYS AS IDENTITY,"
        + " FirstName VARCHAR(20) NOT NULL,
        + " LastName VARCHAR(20),"
        + " Point REAL DEFAULT 0.0,"
        + " BirthDate DATE DEFAULT '1988-12-31',"
        + " ModTime TIMESTAMP DEFAULT '2006-12-31 23:59:59.999')");
      System.out.println("Table created.");
      sta.close();        

      con.close();        
    } catch (Exception e) {
      System.err.println("Exception: "+e.getMessage());
    }
  }
}

When you run this example program for the first time, table Profile will be created. If you run it again, you will get an exception:

C:\herong>\Progra~1\java\jdk1.8.0_45\bin\javac
   -cp .;\progra~1\java\jdk1.8.0_45\db\lib\derbyclient.jar 
   DerbyIdentityColumn.java

C:\herong>\Progra~1\java\jdk1.8.0_45\bin\java
   -cp .;\progra~1\java\jdk1.8.0_45\db\lib\derbyclient.jar 
   DerbyIdentityColumn

Table created.

C:\herong>\Progra~1\java\jdk1.8.0_45\bin\java
   -cp .;\progra~1\java\jdk1.8.0_45\db\lib\derbyclient.jar 
   DerbyIdentityColumn

Exception: Table/View 'PROFILE' already exists in Schema 'APP'.

Last update: 2015.

Table of Contents

 About This Book

 JDBC (Java Database Connectivity) Introduction

 JDK (Java SE) Installation

 Installing and Running Java DB - Derby

 Derby (Java DB) JDBC Driver

 Derby (Java DB) JDBC DataSource Objects

Java DB (Derby) - DML Statements

Tables with Primary Key Column "GENERATED ... AS IDENTITY"

 "INSERT INTO" Statements

 "INSERT INTO" Statements with INDENTITY Columns

 Handling Date and Timestamp Values

 "UPDATE" Statements

 "DELETE FROM" Statements

 Java DB (Derby) - ResultSet Objects of Queries

 Java DB (Derby) - PreparedStatement

 MySQL Installation on Windows

 MySQL JDBC Driver (MySQL Connector/J)

 MySQL - PreparedStatement

 MySQL - Reference Implementation of JdbcRowSet

 MySQL - JBDC CallableStatement

 MySQL CLOB (Character Large Object) - TEXT

 MySQL BLOB (Binary Large Object) - BLOB

 Oracle Express Edition Installation on Windows

 Oracle JDBC Drivers

 Oracle - Reference Implementation of JdbcRowSet

 Oracle - PreparedStatement

 Oracle - JBDC CallableStatement

 Oracle CLOB (Character Large Object) - TEXT

 Oracle BLOB (Binary Large Object) - BLOB

 Microsoft SQL Server 2005 Express Edition

 Microsoft JDBC Driver for SQL Server - sqljdbc42.jar

 Microsoft JDBC Driver - Query Statements and Result Sets

 Microsoft JDBC Driver - DatabaseMetaData Object

 Microsoft JDBC Driver - DDL Statements

 Microsoft JDBC Driver - DML Statements

 SQL Server - PreparedStatement

 SQL Server CLOB (Character Large Object) - TEXT

 SQL Server BLOB (Binary Large Object) - BLOB

 JDBC-ODBC Bridge Driver - sun.jdbc.odbc.JdbcOdbcDriver

 JDBC-ODBC Bridge Driver - Flat Text Files

 JDBC-ODBC Bridge Driver - MS Access

 JDBC-ODBC Bridge Driver - MS SQL Server

 Summary of JDBC Drivers and Database Servers

 Additional Tutorial Notes to Be Added

 Outdated Tutorials

 References

 PDF Printing Version