MySQL add column if not exist error

Question

How do I add a column if not exist in MySQL?

I have tried this, but it doesn't work anymore in the latest MySQL:

IF NOT EXISTS( SELECT NULL
            FROM INFORMATION_SCHEMA.COLUMNS
           WHERE table_name = 'tablename'
             AND table_schema = 'db_name'
             AND column_name = 'columnname')  THEN

  ALTER TABLE `TableName` ADD `ColumnName` int(1) NOT NULL default '0';

END IF;

The error:

[Err] 1064 - You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'IF NOT EXISTS (
    SELECT
        NULL
    FROM
        INFORMATION_SCHEMA.COLUMNS
    WHERE
    ' at line 1

Rahul · Accepted Answer · 2017-03-21 07:57:25Z

3

Sole reason you get that error cause you are trying to run it individually whereas that IF block has to be executed inside a procedure block like below

create procedure usp_addcol
as
begin
IF NOT EXISTS( SELECT NULL
            FROM INFORMATION_SCHEMA.COLUMNS
           WHERE table_name = 'tablename'
             AND table_schema = 'db_name'
             AND column_name = 'columnname')  THEN

  ALTER TABLE `TableName` ADD `ColumnName` int(1) NOT NULL default '0';

END IF;
end;

Now you can just call the procedure.

answered Mar 21, 2017 at 7:57

Rahul

78.1k14 gold badges80 silver badges132 bronze badges

Sign up to request clarification or add additional context in comments.

Collectives™ on Stack Overflow

MySQL add column if not exist error

1 Answer 1

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

Comments

Your Answer

Sign up or log in

Post as a guest

Related