mysql is taking too much time to execute, how to reduce execution time or perform it faster

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i have written a query for mysql database. the result is to display in a Crystal Report.
The problem is, the execution time is too much(more than 30 minutes).
how can i reduce this execution time. Any guidelines is warmly welcome.
below is the c# code...

string strQry = "select distinct category,pay_mode,coalesce((select sum(amount) from sold_items where  invoice_date between '" + dtfrom1 + "' and '" + dtto1 + "' and category = A.category and pay_mode = A.pay_mode and tax_percent = '0.00'),0.00) as taxFree,coalesce((select sum(amount) from sold_items where  invoice_date between '" + dtfrom1 + "' and '" + dtto1 + "' and category = A.category and pay_mode = A.pay_mode and tax_percent = '5.00'),0.00) as amountSub5,coalesce((select sum(amount) from sold_items where  invoice_date between '" + dtfrom1 + "' and '" + dtto1 + "' and category = A.category and pay_mode = A.pay_mode and tax_percent = '14.00'),0.00) as amountSub14 from sold_items A where invoice_date between '" + dtfrom1 + "' and '" + dtto1 + "'";
              
                MySqlDataAdapter da = new MySqlDataAdapter(strQry,con);
               
                DataSet2 ds1 = new DataSet2();
                da.SelectCommand.CommandTimeout = 3600;//60 minutes
                da.Fill(ds1, "saletaxreport1");
                CRSaletaxReport_Initial pr = new CRSaletaxReport_Initial();
                pr.SetDataSource(ds1);
                pr.VerifyDatabase();
                crystalReportViewer1.ReportSource = pr;

below is the value of strQry variable...

select distinct invoice_date,coalesce((select sum(amount) from sold_items B where B.invoice_date = A.invoice_date and B.pay_mode=A.pay_mode and tax_percent = '00.00'),0.00) as taxFree,coalesce((select sum(amount) from sold_items B where B.invoice_date = A.invoice_date and B.pay_mode=A.pay_mode and tax_percent =  '5.00'),0.00) as amountSub5,coalesce((select sum(amount) from sold_items B where B.invoice_date = A.invoice_date and B.pay_mode=A.pay_mode and tax_percent =  '14.00'),0.00) as amountSub14,pay_mode from sold_items A where invoice_date between '2013/11/24' and '2013/11/26' ORDER BY invoice_date

below is my explain plan...
id, select_type, table, type, possible_keys, key, key_len, ref, rows, Extra
1, 'PRIMARY', 'A', 'ALL', '', '', '', '', 102746, 'Using where; Using temporary; Using filesort'
4, 'DEPENDENT SUBQUERY', 'B', 'ALL', '', '', '', '', 102746, 'Using where'
3, 'DEPENDENT SUBQUERY', 'B', 'ALL', '', '', '', '', 102746, 'Using where'
2, 'DEPENDENT SUBQUERY', 'B', 'ALL', '', '', '', '', 102746, 'Using where'

Posted 26-Nov-13 1:13am

Member 9822231

Updated 26-Nov-13 2:30am

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Herman<T>.Instance 26-Nov-13 7:32am

You are doing a lot of subqueries with SUM argument. Why not first store the result of each SUM() part in a temporary variable and then do the select.

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phil.o · Answer 1 · 2013-11-26T01:16:00

Solution 1

Try to put an index on every field involved in your complex query, and see if it does the trick.
I would use phpmyadmin to do that.

Posted 26-Nov-13 1:16am

phil.o

Comments

[no name] 26-Nov-13 7:29am

putting the index is to be done on which side programming or database?

phil.o 26-Nov-13 7:52am

Database one :)
It's a static configuration, I mean you do it once and will not have to come back to it later.

obhijitghosh · Answer 2 · 2013-11-26T01:51:00

Please execute the below and paste the output

explain select distinct invoice_date,coalesce((select sum(amount) from sold_items B where B.invoice_date = A.invoice_date and B.pay_mode=A.pay_mode and tax_percent = '00.00'),0.00) as taxFree,coalesce((select sum(amount) from sold_items B where B.invoice_date = A.invoice_date and B.pay_mode=A.pay_mode and tax_percent =  '5.00'),0.00) as amountSub5,coalesce((select sum(amount) from sold_items B where B.invoice_date = A.invoice_date and B.pay_mode=A.pay_mode and tax_percent =  '14.00'),0.00) as amountSub14,pay_mode from sold_items A where invoice_date between '2013/11/24' and '2013/11/26' ORDER BY invoice_date.

satyaanupama · Answer 3 · 2013-11-26T01:54:00

Solution 4

try to make subtables then give each one to primary key n foriegn key for access. then alternatively u can reduce the complexity... thanku

Posted 26-Nov-13 1:54am

satyaanupama