Removing Columns After Table Creation Using SQL

[ponjavic]

Isn't possible to delete and remove columns after a table has been created?
Rows works just fine but columns don't...

 

[imabug]

in MySQL, this is done with http://dev.mysql.com/doc/mysql/en/ALTER_TABLE.html

 

[master_coda]

Note that columns and rows in a database are very different things, so the fact that you can do something to a row doesn't automatically mean you should be able to do the same thing to a column.


Still, any good database should allow you to delete a column unless you've deliberately added constraints that would prevent it. But you have to modify the table to do that, usually with an ALTER TABLE statement.

 

[so-crates]

You can, but its not considered a good thing to do, except possibly when prototyping. This is because you are altering your schema, which shouldn't happen. Would you want to alter the form of a data structure at runtime?

 

[master_coda]

You can, but its not considered a good thing to do, except possibly when prototyping. This is because you are altering your schema, which shouldn't happen. Would you want to alter the form of a data structure at runtime?

If your schema is wrong, why wouldn't you change it?

 

[poolwin2001]

It is a DDL command and is language specific.