1. SQL 2006 By Cathie Usher

2. SQL

3. Introduction to SQL SQL stands for Structured Query Language In simple terms it is a universal language that permits the construction of tables and the manipulation of Data that lies within a table. SQL is extensively used in many areas of industry and is fast becoming the backbone of Internet display and functionality. In this section we concentrate on the construction and population of tables. This area is referred as the Data Definition Language of SQL (DDL). The following 2 sections concentrate on Data Manipulation Language (DML) where we do the actual queries. You will also be required to create tables yourself and perform some fundamental exercises in the Tutorials.

6. Vocabulary The following terminologies are used in this area of SQL

12. Creating a Table (1) sql> CREATE TABLE DEPARTMENT (DEPT_CODE CHAR(1) NOT NULL, DNAME VARCHAR(25) NOT NULL, MAIL_NO CHAR(2) NOT NULL, PRIMARY KEY (DEPT_CODE));

13. Creating the Table (2) sql> CREATE TABLE EMPLOYEE (EMP_ID CHAR(3) NOT NULL, ENAME VARCHAR(25) NOT NULL, DEPT CHAR(1) NOT NULL, MANAGER CHAR(3), DATE_JOINED DATE, DOB DATE, PRIMARY KEY (EMP_ID), FOREIGN KEY (MANAGER) REFERENCES EMPLOYEE, FOREIGN KEY (DEPT) REFERENCE DEPARTMENT); Note: This table cannot be created until the Department table has been created, as it references the Department table.