Thread: Embedded transactions

Embedded transactions

From
"John Wells"
Date:
On this page: http://www.compiere.org/technology/independence.html, the
project leader of Compiere (a popular ERP package) states that the move to
Postgres failed because of lack of support of embedded
transactions...something both Oracle and DB2 support.

Can someone explain to me excactly what embedded transactions are and why
they're challenging enough to not be included in Postgres or MySQL?  I'm
guessing it's some sort of begin/commit/rollback transactions within
being/commit/rollback blocks, but I may be trivializing it.

Thanks,
John


Re: Embedded transactions

From
Bruce Momjian
Date:
John Wells wrote:
> On this page: http://www.compiere.org/technology/independence.html, the
> project leader of Compiere (a popular ERP package) states that the move to
> Postgres failed because of lack of support of embedded
> transactions...something both Oracle and DB2 support.
>
> Can someone explain to me excactly what embedded transactions are and why
> they're challenging enough to not be included in Postgres or MySQL?  I'm
> guessing it's some sort of begin/commit/rollback transactions within
> being/commit/rollback blocks, but I may be trivializing it.

They want:

    BEGIN;
    INSERT
    BEGIN;
    INSERT;
    -- failure
    ROLLBACK;
    INSERT;
    COMMIT;

so if the insert fails, they can continue with their transactions.  They
are kind of hard to do, but we are working on it:

    http://momjian.postgresql.org/main/writings/pgsql/project

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