[Pgpool-general] Multi-statement queries

[Guillaume Lelarge]

Le 05/03/2010 09:45, Matthias Tief a écrit :
> Hallo,
> 
> we are planning to use pgpool-II as replication solution for our
> PostgeSQL application. Currently we evaluate, whether the restriction of
> pgpool-II affect our application. In the documentation you say:
> "pgpool-II cannot process multi-statement query." What do you exactly
> mean with "multi-statement queries". As I found out you don't mean
> transactions that contain multiple statments, like BEGIN - COMMIT
> blocks. These blocks are "committed" or in case of a failure are "rolled
> back" correctly. I would appreciate if you could give me an example of
> multi-statement queries.
> 

"statement1; statement2; statement3;" in a single trip to the backend.

For example:

"INSERT INTO t1 VALUES (1); INSERT INTO t1 VALUES (2); INSERT INTO t1
VALUES (3);"

is a multi-statement query, whereas

"INSERT INTO t1 VALUES (1);"
then
"INSERT INTO t1 VALUES (2);"
then
"INSERT INTO t1 VALUES (3);"

are three one-statement queries.

pgAdmin uses this quite a lot ("SET client_encoding TO utf8; SELECT *
FROM...").


-- 
Guillaume.
 http://www.postgresqlfr.org
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