How can I insert column comments through a Standard SQL script?

Question

I want a script that inserts table comments and column comments. Said script must be unique and run satisfactorily both on Oracle and MySQL. Furthermore, I prefer it to be written in Standard SQL.

This is how I do it now. But it does not work on MySQL.

comment on table F_Transaction 
    is 'Fact table for system transactions';

comment on column F_Transaction.Transaction_Date
    is 'Date in which the transaction took place';

What SQL construction should I use to achieve my purpose?

Answer 1

The standards do not seem to define any way to define table or column comments (looks like they don't even mention them). So, the syntax for comments on tables/columns can vary from one DBMS to another.

It seems that a number of DBMS agree with Oracle's COMMENT ON syntax (see Oracle create table with column comments).

With MySQL it's necessary to specify the comments along with the table/column definition (in CREATE TABLE or ALTER TABLE sentences). See this related question: Alter MYSQL Table To Add Comments on Columns.