Re: [INTERFACES] Transaction: Begin, Lock

On Mon, Sep 13, 1999 at 10:58:43AM -0400, Margarita Barvinok wrote:
> EXEC SQL CONNECT TO ...
> for (i=2; i<x: i++) {
> strncpy(oid_c, entries[i].val, 10); /* get oid */
> oid_rec = atoi(oid_c);
> EXEC SQL BEGIN WORK;
> EXEC SQL DELETE FROM phonebook
> WHERE oid = :oid_rec;
> EXEC SQL COMMIT WORK;
> }
> EXEC SQL DISCONNECT;
>
> 1. Why i get the following message when I run this code?
> NOTICE: BeginTransactionBlock and not in default state

I take it you did not use 'ecpg -t' did you? The normal situation is that
ecpg creates a auto-transaction mode, i.e. a transaction is started
automatically. You only need to issue a COMMIT once you finish your
transaction resp. a ROLLBACK if you want to cancel it.

So you tell the backend to start a transaction while already inside a
transaction. And that cannot work.

You can either just remove the BEGIN WORK statement or you always give
option '-t' to ecpg.

> 2. How should I lock the table phonebook during this transaction?

Why do you need that? You do not need an explicit lock for the delete to
work.

Michael
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