![]() ![]() Here’s how you add a text field ( varchar): alter table ideas add short_desc varchar(32) after priority Īnd although I wouldn’t do it for this specific example, here’s how you make a new column the first column in a table with the first keyword: alter table ideas add foobar int first įor more information on the MySQL ALTER TABLE “ADD COLUMN” syntax, see the MySQL ALTER TABLE documentation. Here’s a similar alter table add column query, but this time specifying a default value for my integer field: alter table ideas add priority int default 5 after idea Next, making sure I put the new column exactly where I want it: alter table ideas add priority int after idea First, my original idea: alter table ideas add priority int For example, you can atomically rename a column and add a new column with the old. You can also run these commands through a GUI or web interface, like the PhpMyAdmin tool.) Other MySQL ALTER TABLE ADD COLUMN examplesīefore I go back to work, here are some other MySQL ALTER TABLE “add column” examples, showing different approaches. How do I add a column after a particular column in MySQL The syntax to add a column in a table in MySQL (using the ALTER TABLE statement) is: ALTER TABLE tablename ADD newcolumnname columndefinition FIRST AFTER columnname tablename. Some subcommands can be used in combination in a single ALTER TABLE statement. coldefinition specify the definition of the column such as datatype. (Note that I ran all those MySQL commands after logging into my MySQL server and then accessing the database I wanted to alter. 19 MySQL ALTER TABLE does not have the IF EXISTS option. ADD COLUMN colname It adds a new column to the table. Now my MySQL database table looks like this: mysql> desc ideas Īs you can see, the new priority column is right where I want it. I could have added it like this: alter table ideas add priority int īut I wanted it to appear right after the existing idea column, so instead I ran my MySQL ALTER TABLE ADD COLUMN query like this: mysql> alter table ideas add priority int after idea Īs you can see it updated 70 rows in the table. This table already exists, and I wanted to add a new table column named priority. For example, you can add or delete columns, create or destroy indexes, change the type of existing columns, or. | date_created | timestamp | NO | | CURRENT_TIMESTAMP | | ALTER TABLE changes the structure of a table. | category_id | int(11) | NO | MUL | NULL | | | id | int(11) | NO | PRI | NULL | auto_increment | | Field | Type | Null | Key | Default | Extra | I started with a MySQL database table named ideas: mysql> desc ideas Sure, here’s a MySQL “ALTER TABLE ADD COLUMN” example I just ran through. ![]() MySQL alter table FAQ: Can you share some examples of how to use the MySQL ALTER TABLE syntax, especially the ADD COLUMN syntax. ![]()
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