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Problem with reading data from standby server ?

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Hello,

when I read binary replication tutorial (http://wiki.postgresql.org/wiki/Binary_Replication_Tutorial) I see on Hot Standby: Hot Standby is identical to Warm Standby, except that the Standby is available to run read-only queries. I setup hot standby server described in tutorial and it's working fine, no problem with that. I have a problem when I try to start a script that should read whole table, error message from php is:

PHP Warning: pg_query(): Query failed: ERROR: canceling statement due to conflict with recovery DETAIL: User query might have needed to see row versions that must be removed. in dump.php on line 68 PHP Warning: pg_fetch_array() expects parameter 1 to be resource, boolean given in dump.php on line 69 PHP Warning: pg_query(): Query failed: ERROR: canceling statement due to conflict with recovery DETAIL: User query might have needed to see row versions that must be removed. in dump.php on line 235 PHP Warning: pg_fetch_array() expects parameter 1 to be resource, boolean given in dump.php on line 236


Script actually start sql query:

SELECT abs.id, array_accumulate(abs.status) AS status, array_accumulate(abs.service) AS service, stb.model FROM statuses abs, stb_tbl stb WHERE abs.id = stb.ser AND abs.service != 8 AND abs.id LIKE '432%' GROUP BY abs.id, stb.model ORDER BY abs.id


array_accumulate aggregate is:


CREATE AGGREGATE array_accumulate (
    sfunc = array_append,
    basetype = anyelement,
    stype = anyarray,
    initcond = '{}'
);


When data is fetched it's saved into a file after some modifications. This script is work a 30-40 min until all data is parsed. Well, I think problem is started when master server send new wal file to slave, but how I can resolve that problem ?



Any solutions or some one to can point me how I can resolve this problem ?


Regards,
Condor

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