To: Mohamed Hashim <nmdhashim@gmail.com>
cc: tv@fuzzy.cz, ktm@rice.edu, Marcus Engene <mengpg2@engene.se>,
	pgsql-performance@postgresql.org
Subject: Re: Performance Problem with postgresql 9.03, 8GB RAM,
	Quadcore Processor Server--Need help!!!!!!!
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Comments: In-reply-to Mohamed Hashim <nmdhashim@gmail.com>
	message dated "Wed, 02 Nov 2011 12:42:20 +0530"
Date: Wed, 02 Nov 2011 10:26:50 -0400
Message-ID: <29599.1320244010@sss.pgh.pa.us>
From: Tom Lane <tgl@sss.pgh.pa.us>

Mohamed Hashim <nmdhashim@gmail.com> writes:
> The below are the sample query which i put for particular one bill_id

> EXPLAIN ANALYZE SELECT abd.bill_no as
> bill_no,to_char(abd.bill_date,'dd/mm/yyyy') AS date,mp.product_desc as
> product_desc,std.quantity,std.area,rip.price AS rate
> FROM acc_bill_items_106 abi
>     JOIN acc_bill_details_106 abd ON abd.bill_id=abi.bill_id
>     JOIN stk_source ss ON  ss.source_detail[1]=1 and
> ss.source_detail[2]=abi.item_id
>     JOIN stock_transaction_detail_106 std ON std.stock_id=ss.stock_id
>     JOIN stock_details_106 sd106 ON sd106.stock_id=std.stock_id
>     JOIN master_product_106 mp ON mp.product_id= sd106.product_id
>     JOIN receipt_item_price_106 rip ON rip.receipt_item_id=abi.item_id
>     WHERE abi.bill_id=12680;

All the time seems to be going into the seqscan on stk_source and its
child tables.  It looks like it would help if "ss.source_detail[1]=1 and
ss.source_detail[2]=abi.item_id" were indexable (particularly the
latter).  Which probably means you need to rethink your data
representation.  Putting things that you need to index on into an array
is not a very good design.  I suppose you can do it if you're absolutely
set on it (functional indexes on (source_detail[1]) and (source_detail[2]))
but it appears to suck from a notational point of view too.  Six months
from now, when you look at this code, are you going to remember what's
the difference between source_detail[1] and source_detail[2]?  Not
without consulting your notes, I bet.

			regards, tom lane