Re: Online system & transactions

ray(at)unreal64(dot)net ("Lada 'Ray' Lostak") writes:
> Imagine some online system, based on PgSql. There are 'many' parts which
> depends on each other. I will give small example, but instead of simple
> table imagine changing tenths various tables (editing). So, 'change table A'
> can be work for hours.
>
> There are tables tableA and tableB. Changes are made by thin client. If
> you change tableA, you have to also change tableB to 'finish' operation.
> Between starting changing tableA until tableB is finished, data are 'not
> valid'. Record may be changes, deleted, inserted, whatever.
>
> Is there any simple way, how to create 'transactions' over database
> connections ? These relations are really complex in real live and doesn't
> fit table foundaries, so, it is basically not realistic to make it on
> application layer and need to be done somehow on DB layer....
>
> The best solution should be possibility to 'begin' transaction, 'store'
> somehow on server, and next time, instead of begin new transaction return to
> stored one. Transactions solves all these problems, but they don't work
> across various/multiple connections....
>
> Any ideas/references please ?

You probably should look at the documentation for this.

<http://www.postgresql.org/docs/current/interactive/sql-begin.html>

PostgreSQL supports _exactly_ this notion, in exactly the way you
describe.

If you need to have multiple transactions active at once, you will
just need to establish multiple connections.
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