Adding columns

Senior WebHelper Joined: 21 Apr 2003 Posts: 153

How do I add a column to a table once I have already created the table?

WebHelper Joined: 01 Mar 2003 Posts: 69 Location: Texas

Here's a link you might find helpful:

MySQL Manual

Specifically:

Code:

ALTER [IGNORE] TABLE tbl_name alter_spec [, alter_spec ...]

alter_specification:
ADD [COLUMN] create_definition [FIRST | AFTER column_name ]
or ADD [COLUMN] (create_definition, create_definition,...)
or ADD INDEX [index_name] (index_col_name,...)
or ADD PRIMARY KEY (index_col_name,...)
or ADD UNIQUE [index_name] (index_col_name,...)
or ADD FULLTEXT [index_name] (index_col_name,...)
or ADD [CONSTRAINT symbol] FOREIGN KEY [index_name] (index_col_name,...)
[reference_definition]
or ALTER [COLUMN] col_name {SET DEFAULT literal | DROP DEFAULT}
or CHANGE [COLUMN] old_col_name create_definition
[FIRST | AFTER column_name]
or MODIFY [COLUMN] create_definition [FIRST | AFTER column_name]
or DROP [COLUMN] col_name
or DROP PRIMARY KEY
or DROP INDEX index_name
or DISABLE KEYS
or ENABLE KEYS
or RENAME [TO] new_tbl_name
or ORDER BY col
or table_options

Simple example:

Code:

Alter table some_table add (new_column_definition);

Dave