SQL SERVER - TABLES (CONT.)

Description

The SQL Server (Transact-SQL) ALTER TABLE statement is used to add, modify, or drop columns in a table.

Add column in table

You can use the ALTER TABLE statement in SQL Server to add a column to a table.

Syntax

The syntax to add a column in a table in SQL Server (Transact-SQL) is:

ALTER TABLE table_name
  ADD column_name column_definition;

Example

Let's look at an example that shows how to add a column in an SQL Server table using the ALTER TABLE statement.

For example:

ALTER TABLE employees
  ADD last_name VARCHAR(50);

This SQL Server ALTER TABLE example will add a column to the employees table called last_name.

Add multiple columns in table

You can use the ALTER TABLE statement in SQL Server to add multiple columns to a table.

Syntax

The syntax to add multiple columns to an existing table in SQL Server (Transact-SQL) is:

ALTER TABLE table_name
  ADD column_1 column_definition,
      column_2 column_definition,
      ...
      column_n column_definition;

DROP TABLE

Description

The SQL Server (Transact-SQL) DROP TABLE statement allows you to remove or delete a table from the SQL Server database.

Syntax

The syntax for the DROP TABLE statement in SQL Server (Transact_SQL) is:

DROP TABLE table_name;

Parameters or Arguments

table_name

The name of the table to remove from the SQL Server database.

Example

Let's look at an example that shows how to drop a table using the DROP TABLE statement in SQL Server (Transact-SQL).

For example:

DROP TABLE employees;

This DROP TABLE example would drop the table called employees from the current database in SQL Server.