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Hi,
I tried to download the above DB..but was not able too. Yes, Access is difficult in the beginning, specially when it returns 'no' data. The key here is to be patient, and I would suggest the following:
1. You have three (3) tables --- Customers ; Rentals ; Media. Dont Query these tables togethar initially. This is just to 'test' your data. Just run simple select queries on these tables [wont take too long]..and see what Access is returning. The reason you are probably not getting recordsets on your complex queries is because your joins..are incorrect or data types do not match...! For example on Customer data run a simple query selecting customers with last name SMITH. Or Customers with phn number as NULL. See how these queries are running.
2. Is the Customer ID in your Rentals and Customers tables exactly the same..data types. Even if there is a padding of zeroes in the beginning...Access will see them differently. 00034 <> 34 for Access. Check the same for MEDIA in the Media and Rentals tables. The key here is that..your table structures should be clear to you...and each data type..should be explicitly defined by you for the tables. If you do not do this..Access takes them as defaults..which at times causes problems when querying. Be really carefull with dates....Access at times...converts them to TEXT....!
3. JOINS. There are three types of joins in Access. For example if you have two tables....TableonLEFT and TableonRIGHT. If you join them..using a common field. Then you double click on the join..you get three options. The INNER JOIN is when you choose the first option. This will only show records...that present in both tables. The LEFT join is when you choose the middle option. This will show ALL records from the LEFT table..and those records from the RIGHT table which equal any record on the LEFT TABLE. So if the left table has 1000 records..and 20 of those...are present in the right table. The left join..will show 1000 recordsets....! And the RIGHT JOIN works the other way round. It will show all records from the right side table..and those matching from the left side table.
Play around with simple SELECT queries...and see how the joins..work....trying out INNER LEFT AND RIGHT. The basic rule is..."if you can SELECT it correctly ---- you can manage it perfectly......!"
take care...and let us know..where else you need help...
regards,
Asingh
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