How to Create a tables in SQL?

[sam]

This is the format of a simple create table statement:

create table "tablename"
("column1" "data type",
"column2" "data type",
"column3" "data type");

Format of create table if you were to use optional constraints:

create table "tablename"
("column1" "data type"
[constraint],
"column2" "data type"
[constraint],
"column3" "data type"
[constraint]);
[ ] = optional

Note: You can have as many columns as you require, and the constraints are optional.

Example:

create table workers
(first varchar(15),
last varchar(20),
age number(3),
address varchar(30),
city varchar(20),
state varchar(20))


To create a table, enter the keywords create table followed by the table name, followed by an open parenthesis, followed by the first column name, followed by the data type for that column, followed by any optional constraints, and followed by a closing parenthesis. It is important to use an open parenthesis before the beginning table, and a closing parenthesis after the end of the last column definition. Make sure you seperate each column definition with a comma( , ) . All SQL statements should end with ";".

The table and column names must start with a alphabet and can be followed by numbers, or underscores - not to exceed 30 characters in length. Do not use any SQL reserved keywords as names for tables or column names (such as "select", "create", "insert", etc).

Data types specify what the type of data can be for that particular column. If a column called "Last_Name", is to be used to hold names, then that particular column should have a "varchar" (variable-length character) data type.

[linux tech]

You can also have a look at simple as well as unique indexes.

Simple Indexes -

CREATE INDEX index_name
ON table_name (column_name)

Unique Indexes -

CREATE UNIQUE INDEX index_name
ON table_name (column_name)