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Structured Query Language Made Simple
Fukula Hastings Nyekanyeka

Defining Data
Creating New Tables

All tables within a database must be created at some point in time...let's see how we would create the Orders table:

CREATE TABLE ORDERS
(OWNERID INTEGER NOT NULL,
ITEMDESIRED CHAR(40) NOT NULL);

This statement gives the table name and tells the DBMS about each column in the table. Please note that this statement uses generic data types, and that the data types might be different, depending on what DBMS you are using. As usual, check local listings. Some common generic data types are:

  • Char(x) - A column of characters, where x is a number designating the maximum number of characters allowed (maximum length) in the column.
  • Integer - A column of whole numbers, positive or negative.
  • Decimal(x, y) - A column of decimal numbers, where x is the maximum length in digits of the decimal numbers in this column, and y is the maximum number of digits allowed after the decimal point. The maximum (4,2) number would be 99.99.
  • Date - A date column in a DBMS-specific format.
  • Logical - A column that can hold only two values: TRUE or FALSE.
One other note, the NOT NULL means that the column must have a value in each row. If NULL was used, that column may be left empty in a given row.