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SQL Drop Table

SQL Drop Table

shape Description

SQL Drop Table command can be performed on existing database. Indexes, tables, and databases can easily be erased/evacuated with the DROP statement. The following are the actions performed by drop command.
  • Dropping a section from the table.
  • Dropping a table from the database.

Dropping a column from the table

shape Syntax

Alter table drop column;
Table_name => Any accurate table. Column_name =>The operation that  can be performed on a column in the table.

shape Examples

By viewing the below example, the concept of drop command can be understood easily. [c]sql> desc student; +------------+--------------+------+-----+---------+-------+ | Field | Type | Null | Key | Default | Extra | +------------+--------------+------+-----+---------+-------+ | stu_id | int(11) | YES | | NULL | | | stu_name | varchar(255) | YES | | NULL | | | stu_result | varchar(255) | YES | | NULL | | | branch | varchar(255) | YES | | NULL | | | fee | int(11) | YES | | NULL | | +------------+--------------+------+-----+---------+-------+ 5 rows in set (0.00 sec) sql> alter table student drop column fee; Query OK, 0 rows affected (0.53 sec) Records: 0 Duplicates: 0 Warnings: 0 sql> desc student; +------------+--------------+------+-----+---------+-------+ | Field | Type | Null | Key | Default | Extra | +------------+--------------+------+-----+---------+-------+ | stu_id | int(11) | YES | | NULL | | | stu_name | varchar(255) | YES | | NULL | | | stu_result | varchar(255) | YES | | NULL | | | branch | varchar(255) | YES | | NULL | | +------------+--------------+------+-----+---------+-------+ 4 rows in set (0.00 sec)[/c] The above example tells that, how to drop a column_name fee from the table.

Dropping a table from the database

shape Syntax

drop table <table name>;

shape Examples

By viewing the below example, the concept of SQL Drop Table command can be understood easily.
[c]sql> desc student; +------------+--------------+------+-----+---------+-------+ | Field | Type | Null | Key | Default | Extra | +------------+--------------+------+-----+---------+-------+ | stu_id | int(11) | YES | | NULL | | | stu_name | varchar(255) | YES | | NULL | | | stu_result | varchar(255) | YES | | NULL | | | branch | varchar(255) | YES | | NULL | | +------------+--------------+------+-----+---------+-------+ 4 rows in set (0.00 sec) sql>drop table student; Query OK, 0 rows affected (0.48 sec) sql> select * from student; ERROR 1146 (42S02): Table 'employee.student' doesn't exist[/c] The above example tells that, how to drop all the columns from the table student. SQL Drop Table is used to drop table from a database. It removes the table from the database schema, there is no way to recover the data after execution of this statement on the table.

Summary

shape Key Points

  • SQL Drop Table - SQL Drop Table will drop a column from the table and drop table will drop the entire table.