SQL Create Command

This command is used to create a table. The syntax of this command is:

create table tablename
(column1name datatype [constraint],
column2name datatype [constraint], 
column3name datatype [constraint]);

Keywords specifying Items that may be created

• table

Data Types

• char(size) - Fixed length string of characters of the set size. The size of the string is limited to 255 characters.
• date
• number(maxsize) - Number with a maximum number of digits specified by "maxsize".
• number(maxdigits,maxright) - A decimal number with a manimum number of "maxdigits" with "a maximum number of digits to the right of the decimal, "maxright".
• varchar(maxsize) - A character string with variable lingth limited to "maxsize".

Constraints

Constraints are rules for the column.. Possible values include:

• not null - The column values must have a value and cannot be null.
• primary key - Each record is uniquely identified by this column.
• unique - No two values may be the same in the column

Example

create table citylist
(name varchar(20),
state varchar(20),
population number(8),
zipcode number(5) unique);