command used to change the contents of the primary key ?

You can use

RENAME

but this operation might take a very long time.
For normal it is better to create a new record and delete the old one. But it depends on what you exactly want to do.

einsTeIn.NET wrote:

For normal it is better to create a new record and delete the old one. But it depends on what you exactly want to do.

No most definately NOT the way to go for regular code. There is a reason why there is a RENAME operation, it takes care of all table relationships for you. Only go the delete/insert route if you know ALL relationships and you explicitly take care of those yourself. Other than that, as a general rule you should always use RENAME.

You said:

einsTeIn.NET wrote:

For normal it is better to create a new record and delete the old one.

Which I interpreted as an advice from you that you think this is "the normal, regular, recommended" way to do this, when in fact it is a "last resort, only in exceptional cases, and only if you are well aware of all implications" way of doing it.

You cannot tell whole truth each time... ;-) People must be prepared for whole truth... Give the whole truth into hand of unprepared man and he will screw it and use it as he wish, mainly if it can hurt someone... :whistle: