On 01/03/18 05:35, Peter Eisentraut wrote:
> The SQL standard offers the "chained transactions" feature to address
> this. The new command variants COMMIT AND CHAIN and ROLLBACK AND CHAIN
> immediately start a new transaction with the characteristics (isolation
> level, read/write, deferrable) of the previous one. So code that has
> particular requirements regard transaction isolation and such can use
> this to simplify code management.
Oh, is that all it does? That's disappointing, because that's a lot less
powerful than how I understand chained transactions. And at the same
time relieving, because that's a lot simpler to implement :-).
In Gray & Reuter's classic book, Transaction Processing, they describe
chained transactions so that you also keep locks and cursors.
Unfortunately I don't have a copy at hand, but that's my recollection,
at least. I guess the SQL standard committee had a different idea.
- Heikki