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Old 09-29-03, 09:39
Ifx_Loco Ifx_Loco is offline
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Question details on sequential scans

Hi!

I've an application that stores a lot of data in my database-tables (Informix DS 9.30). As there are some problems with the performance, I analyze, among other things, the parameter seqscans (given by onstat -p) and which tables causes them (script: "select tabname, seqscan, nrows from sysptprof a, sysptnhdr b where seqscans > 100 and dbsname = 'DB' and a.partnum=b.partnum order by seqscans desc").
The "SET EXPLAIN ON"-Statement shows the usage of "INDEX PATH" when executing the queries. But there are a lot of seqscans on specific tables.

I like to put the following question:
How can I retrieve information about the SQL-Statement, that cause the sequential scan on a table?

Any help and suggestions would be appreciated.
Thanks in advance!
Thomas
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Old 09-30-03, 05:54
Roelwe Roelwe is offline
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Check this out:

select * from syssqexplain

important fields:
sqx_seqscan

The following table will show you the current sql statements running:
select * from syssqlstat;
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