The Power of Queries

OK, Then:

I tried yesterday to give you print screens of all the queries we were supposed to discuss in our blogs with comments under each one. Today, when I tried to edit yesterday's blog the print screens showed up as the link Photo but when I tried to open them I couldn't get back to my comments. I got kicked out of Blogger. I guess attaching 8 different print screens was just too much!

Parameter Query

I can see how important it might be to select only a small piece of information from a database that is huge. This can be done with either a filter or a query. I guess the benefit of a parameter query is that the next time you use it you can choose any criteria you want within the parameter fields. You don't have to set up a new filter to get different information.

Find Duplicate Query

I wish I had more experience with databases. I'd be better able to appreciate the amount of time these queries might save. if I were trying to look up orders by customers and I had more than one record for one customer I might have the orders in different places and not be able to see all the orders for just one customer. I'd want to find the customer which were duplicated right away.

The thing is I would be more likely to have the same customer under two slightly different spellings, in which case a query for a specific customer value wouldn't show the slightly different spelling. With a filter you might be able to see multiple but slightly different values for the same customer. Make sense?

Find Unmatched Records

I can see the value of this query in the example given at the top of page 149 in our text. If there were products that no customer had purchased obviously I'd want to get rid of them. However, in my application, it's hard for me to imagine a circumstance where I had information for a grant at one point in time but didn't have the same information at another point in time but I guess it could happen.

Bottom line is you can't filter for a value that's not there. You can only try to identify a value that's not in a table by comparing it to another table that has the value.

Create New Table Query

If I need a new table based on a select set of data it's much easier to create a query than to have to manually set up a filter for each field (column).

Delete Query

It's certainly faster to delete multiple values using a delete query than to select the records by hand individually. However, with a filter the records you want to delete aren't gone permanently. A delete query would work better in some situations. Filtering would work better in others.

Add Records Query

I can't think of a reason why I'd want to add more records to my grant database. I certainly wouldn't want any duplication of data. Also, if I want to add records to a table why couldn't I just coppy the records from one table to another?

Update Query

This appears to be similar to the edit find edit replace commands in Excel. It's slick.

Crosstab Query

I can see where this would be useful if you just had two criteria for which you wanted to run a function, one criteria for the horizontal axis and one criteria for the vertical axis. I'd like to see how we can use/summarize/examine several criteria at once in aa Access table, like the Excel pivot table. Is this possible, Sage?