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sql - Choose AS400 query records directly from Excel

I've been searching the internet for hours trying to figure out if the following is even possible:
To choose the AS400 query records directly from Excel.

I haven't found any solution or description of how this could be achieved, which makes me guess that it's simply not possible. However, I haven't seen anyone confirm that it is impossible.
So my question is: Is this possible? And if it is, could you point me in the right direction in order for me to start learning how to do it?

I know its possible to run a query from Excel, and then adding parameters via SQL statements, but in my case, this presents several problems that could be avoided by choosing the records before the query is executed.

Example:
I have a query with a column (lets call it ColVal) that can hold the values 1 and/or 2. In the AS400 program under the menu "Work with queries" and then "Choose records" I can specify which records the query should contain when it has run based on the value in ColVal. This means i can get three different situations (A, B and C) when i run the query:

A) The query only contains records where the value in ColVal is 1
B) The query only contains records where the value in ColVal is 2
C) The query contains records where the value in ColVal is either 1 or 2

The goal is to be able to choose which situation I want from Excel in order to circumvent opening and using the AS400 program.
However, using situation C and then editing the query in Excel with an SQL statement to mimic situation A or B is not an option, as this means the query still contains undesired records.

This whole thing boils down to the following: Is it even possible to run the query from Excel essentially changing the data it contains and not just outputting it to excel? If this is possible, is it then possible to pass a parameter to the AS400 system and use it to create situation A, B or C?

I hope this example makes sense.

Edit - New example

Say i have different customers A and B. I can open the AS400 program and run a query in which i have specified that I only want data on customer A. I can then open Excel and use filters (as Hambone described) on the query to determine which records I want to output. However, if I want to work with data from customer B, I have to open the AS400 again and run the query with different parameters. I would like to be able to "change" my dataset from customer A to B from Excel, without having to include both in my recordset and then filter out one of them.

I imagined this is doable if you could pass a parameter to the AS400. The AS400 then runs the query using this parameter as the criteria for which records should be stored in the query. This means that if the parameter is Customer B, then there is no way to acces data from customer A, without running the query through AS400 again.

Any ideas are greatly appreciated :)

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Follow up to my comment, here is a quick primer on how to run an ODBC query directly in MS Excel using Microsoft Query. This is very different than Power Query, which you referenced, in that MS Query is standard with Excel -- it's not a plug-in. This is relevant because it means everyone has it. If you are deploying a solution to others, that's an important consideration.

To start an MS Query in Excel, go to the data tab, select "From Other Sources" -> "Microsoft Query."

enter image description here

A list of your ODBC connections will come up. Pick the one that you want and select "OK."

enter image description here

It may or may not ask you for a login (depending on which ODBC connection you use and how its configured).

enter image description here

The next part is important. MS Query is going to try to have you use its builder to create the query. If you have the SQL, skip this part. It's horrible. Click "Cancel" on the query wizard, and then click the "SQL" button to enter your own SQL. If you can, make sure the result set is small (like use where 1 = 2 in the query).

enter image description here

When MS Query returns results, click the button next to the SQL Button to have it return the results to the spreadsheet. It looks like a little door.

From here, any time you want to refresh the query, you can simply right-click the data table in Excel and select "refresh." Alternatively you can go to the data tab on the ribbon and select "Refresh."

By the way if you have linked pivot tables and charts, the "Refresh All" option will refresh those as well, in the correct order.

To edit your query at any time, right-click on the table in Excel, go to Table-External Data Properties:

enter image description here

Then Click on the Connection Properties icon (highlighted below)

enter image description here

Click on the second tab (Definition) and edit the SQL Directly.

Parameters can be declared simply by inserting a bare "?" in place of your literal.

In other words, if your query looks like this:

select *
from users
where user_id = 'hambone'

Just change it to:

select *
from users
where user_id = ?

Excel will prompt you for a user id before it runs the query. From here, you also have the option of putting the parameter value in a cell within the spreadsheet and having the query read it from there. You'll see these when you right-click the table and go to the "Parameters" menu option.

enter image description here

Let me know if this helps or is unclear.

-- EDIT 7/23/2018 --

To follow up on your latest edit, it is possible to handle the scenario you describe, where you want to be able to filter on a value, or if none is given, then not have a filter. You see this a lot when you present multiple filter options to the user and you want a blank to mean "no filter," which is obviously counter to the way SQL works.

However, you can hack SQL to still make it work:

select * from activities
where
 (activity = ? or ? is null) and
 (energy = ? or ? is null)

In this example you have to declare four parameters instead of two, two for each.

You might also have to play with datatypes, depending on the RDBMS (for example for numerics you might have to say ? = 0 instead of ? is null or even ? = '' for text).

Here is a working example where a single filter was applied on the query above and you can clearly see the second one did not have an impact.

enter image description here


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