Subject Re: DDL and DML in the one transaction
Author Adam
> Adam mentioned in the post 'dbExpress and transactions' that mixing
DDL and
> DML in the one transaction will cause 'funny' things to happen, can
someone
> please elaborate on this - what's going to / could happen?
>

A lot of the time you will get away with it, the problems start when
you create a field in a table then try and populate it with data
before you commit, that sort of thing.

If you add a field to TableA, then update TableB (and TableB has no
triggers that affect TableA), then there is no problem.

Values that you **think** are populated may not be. Give it a go
yourself one day when you are bored. Queries like update table set
somedate = 'now' also behaves unexpectedly.

In short, it is more likely to cause data inconsistencies than some
half upgraded database.

Adam