JOIN Query very slow

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Tally.NET

Hello,

I have the following Input tables

Table1
Serial Item Date SerialandDate
123 Item1 01-04-2007 12339173
123 Item2 01-06-2010 12340330
234 Item1 01-10-2006 23438991
234 Item3 02-04-2010 23440270
234 Item2 01-01-2009 23439814


Table2
Serial Date SerialandDate
123 01-06-2010 12340330
234 02-04-2010 23440270


and i am looking at an Output as below

Serial Item BillDate
123 Item2 01-06-2010
234 Item3 02-04-2010



I am trying this SQL (MS Access 2003) however the query is taking too long to process and the system does not respond.

SELECT Table2.[Serial], Table2.[BillDate], Table1.Item
FROM Table1 INNER JOIN Table2 ON Table1.SerialandDate = Table2.SerialandDate;

There are about 25000 records in both the tables.


ITCat
 
If that is the whole data you have and if the query is not instantaneous (human perception), I suspect something is wrong either with the file itself (try to compact the db? if the same problem, try to copy the file somewhere else on the hard disk and try on this copy? ) either the data is on another PC and the connection is very poor, either the PC itself is damaged (Registry, or hard disk, ...). Try on another PC, if possible, to see if the problem is the same. If there is no problem on that other PC, then it would be a good indication that Access itself is not directly responsible (unless its installation has been compromised).

Vanderghast, Access MVP



Hello,

I have the following Input tables

Table1
Serial Item Date SerialandDate
123 Item1 01-04-2007 12339173
123 Item2 01-06-2010 12340330
234 Item1 01-10-2006 23438991
234 Item3 02-04-2010 23440270
234 Item2 01-01-2009 23439814


Table2
Serial Date SerialandDate
123 01-06-2010 12340330
234 02-04-2010 23440270


and i am looking at an Output as below

Serial Item BillDate
123 Item2 01-06-2010
234 Item3 02-04-2010



I am trying this SQL (MS Access 2003) however the query is taking too long to process and the system does not respond.

SELECT Table2.[Serial], Table2.[BillDate], Table1.Item
FROM Table1 INNER JOIN Table2 ON Table1.SerialandDate = Table2.SerialandDate;

There are about 25000 records in both the tables.


ITCat
 
Oops! i said they were tables, sorry they were Queries. I converted them to
tables and now its working fine.

I'm not sure what caused the slowdown.

Thanks for the inputs.
Praveen

Marshall Barton said:
Tally.NET said:
I have the following Input tables

Table1
Serial Item Date SerialandDate
123 Item1 01-04-2007 12339173
123 Item2 01-06-2010 12340330
234 Item1 01-10-2006 23438991
234 Item3 02-04-2010 23440270
234 Item2 01-01-2009 23439814


Table2
Serial Date SerialandDate
123 01-06-2010 12340330
234 02-04-2010 23440270


and i am looking at an Output as below

Serial Item BillDate
123 Item2 01-06-2010
234 Item3 02-04-2010



I am trying this SQL (MS Access 2003) however the query is taking too long
to process and the system does not respond.

SELECT Table2.[Serial], Table2.[BillDate], Table1.Item
FROM Table1 INNER JOIN Table2 ON Table1.SerialandDate =
Table2.SerialandDate;

There are about 25000 records in both the tables.
Click to expand...


The most important thing you can do is to make sure that you
have an index on the fields using in the ON clause. You do
that in the tables' design view by using the View - Indexes
menu item.
Click to expand...
 
Assuming that SerialAndDate is a combination of the fields Serial and Date, I
would use a query like the following and ignore the SerialAndDate field.

SELECT Table1.Serial, Table1.Item, Table1.Date
FROM Table1 INNER JOIN Table2
ON Table1.Serial = Table2.Serial
AND Table1.Date = Table2.Date

John Spencer
Access MVP 2002-2005, 2007-2010
The Hilltop Institute
University of Maryland Baltimore County
 
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