It’s probably more common for people to edit MySQL tables using a more visual tool such as phpMyAdmin but it is possible to use a manually written SQL query instead to modify tables (this is what a tool like phpMyAdmin does in the background). This post shows how to drop a column from a MySQL table with a SQL query.
Drop a single column
The query to drop a single column is very simple. In the example table "test" there is a field called "foo" that is to be dropped. This is done like so:
ALTER TABLE test DROP COLUMN foo;
Depending how large the table is this may take a few milliseconds to a number of minutes to run.
Drop multiple columns
Multiple columns can be dropped with a single query by simply comma separating a list of DROP COLUMN statments. To drop both the "foo" and "bar" columns from the "test" table do this:
ALTER TABLE test DROP COLUMN foo, DROP COLUMN bar;
As many additional columns can be added to the list as required. Again, this may only take a few milliseconds to many minutes depending on the size of the data in the table.
