Tested with 8.2.3:

Actually you can't DECLARE a cursor outside a transaction:

test1=> declare c1 cursor for select * from dbit2;
ERROR:  DECLARE CURSOR may only be used in transaction blocks

That's the main reason why we don't use DECLARE CURSOR...

I understand we could use DECLARE CURSOR when a FOR UPDATE is
detected, to allow UPDATE/DELETE WHERE CURRENT OF - these only
make sense inside a transaction...

But for normal cursors, we need to support multiple active result
sets that can last outside a transaction block.

Basically, we need all what you can do with ODBC cursors.

Anyway, thanks for your help.


Tom Lane wrote:
Sebastien FLAESCH <[EMAIL PROTECTED]> writes:
Does a simple PQPrepare() with a SELECT statement not create a cursor on
the server side?

No.  A prepared statement is just a query plan, not a query-in-progress.

The Bind/Execute messages sent by PQexecPrepared create something akin
to a cursor, but libpq doesn't expose any API for fetching one row at a
time in that context, so there's no way to use the "current row" anyway.

                        regards, tom lane

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