I have a query with 4 calculated fields , one of them calculate the running sum using DSum
When running this query and go to the last record it is taking some time (that is normal and OK)
But the problem is that MS Access recalculate this field every time I scroll up or down using mouse wheel, and this recalculation taking a very long time that make this query unusable
I think MS Access do this recalculation because it is multi user application so I change it to Exclusive (File > Options > Client Settings > Advanced > Default open mode > Exclusive) , but this not help
So Im looking for something like Excel to disable automatic calculation and calculate what you need and when you need using VBA for MS Access or at least prevent MS Access from recalculate the query every time I scroll up or down.
no more than one user will use my database at the same time
the query has about 40,000 records
As Nick wrote, you can't.
To view the data without recalculation, put it into a report, or use a INSERT INTO or SELECT INTO action query to save it to a temporary table. The latter is especially useful, if you want to do further calculations on the data, or if it is the recordsource of another query.
Related
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 :)
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."
A list of your ODBC connections will come up. Pick the one that you want and select "OK."
It may or may not ask you for a login (depending on which ODBC connection you use and how its configured).
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).
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:
Then Click on the Connection Properties icon (highlighted below)
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.
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.
Yes it's possible. You need to use an ODBC driver to connect to the AS400 and retrieve the data. The driver and documentation are Here
using excel 2013 I need to create a search of a SQL tbl on network SQL server for a specific tag and within a given date range. for instance: the tbl has every make of Chevy made since 1990 and the units sold each day. an example, search for corvette with a date range of 1Jul2017 to 31Jul2017. the result would show up how many corvettes were sold for each day in July of 2017 and I will need to have the total sold for entire month of July.
this in important: I only want them to access the data NOT be able to make changes to database
I can do this in SQL no problem, but I have to do this so someone who does not have access to the SQL database can use this query and get the information they need. the eventual goal is to have an Access frontend for this.
edit: I am no expert in either Excel or SQL but know enough to get some things done. one of the many hats I wear . . .
thanks,
In Excel, Data tab, New Query, From Database, pick the type of database, add connection info, click Advanced options, put your query in the SQL statement window, hit OK, hit Load. Now you have SQL results in a spreadsheet. If you want them to update regularly, go to Data tab again, Connections, select the connection you just made from the list, click Properties, and set it to refresh every hour, or when opening the file, or whatever makes sense to you.
This will only work for users that have permissions to the database. If you need it to be more secure (not hold data in the spreadsheet at all, but only access it from the database), in the connections properties click Refresh data when opening the file, then click Remove data from the external data range before saving the workbook.
I want to delete all the rows from a table that haven't been red or haven't been created within the last year.
There is no column that indicates the last access date of a row.
Is there a way to accomplish this anyway the using some internal logs or anything like this in MS Access?
There is no way to do this. Access doesn't keep this sort of log (or any DBMS I know of).
You would need a "date_created" or "date_accessed" column to achieve this.
BTW, in a continuous form or datasheet view, all rows are read (or the filtered ones).
tldr: Can not update records from query because of aggregate functions. What workarounds do you suggest?
I have a table containing decision criteria to which a user can assign a relative weight. I calculate the absolute weight in an SQL query using an aggregate function (as described here Divide the value of each row by the SUM of this column).
qryDecisionCriteria
name relative_weight absolute_weight (calculated)
price 2 50 %
quality 1 25 %
experience 1 25 %
I would like to present the query result in a form, where the user can update the relative weights, and then sees the absolute_weights.
However, the query results are not updatable, because the query involves an aggregate function.
What alternative methods or workarounds could I use, so that a user can edit relative_weights and view absolute_weights as a kind of visual feedback?
I read about temporary tables here http://www.fmsinc.com/MicrosoftAccess/query/non-updateable/index.html but I'm not sure, how to implement this.
Maybe I could also create an additional "edit form" based on a simple query, that is automatically invoked when the user selects a record in qryDecisionCriteria data?
Or maybe just display data from two queries (one updatable, one with the calculated field) next to each other in the form?
Which options would you recommend and why?
Make the Record Source for the form the updatable base query. In the text box which shows the calculated absolute weight set the control source to
=DSum("relative_weight","<base table name>")/Forms!<Form Name>!relative_weight
You'll need to be sure that you do two things with this
When you drag fields onto a form in Access it makes the name of the control the same as the control source column. this is really annoying and can cause a lot of headaches. Rename your control to something like txtColumnName. That way Forms!<Form Name>!relative_weight is guaranteed to reference the field and not the textbox.
in the AfterChange event for the relative_weight textbox you should add an event handler in which the following code is run
txtabsolute_weight.Requery
This will make sure the formula is recalculated whenever someone changes a weight. Otherwise they need to hit F5.
I need help in creating an query interface with access database.
In brief, with this query interface I want to see calculated future dates for different steps of a process based on the date the process actually started.
The future dates will always be at a fixed number of days after the start date. I hope I am able to explain this in an understandable manner.
I was thinking of using access forms? Please help me in this. I am not sure of how to proceed with this.
If your data is already in MS Access, then using Access Forms would be your easiest method of displaying that data. If the data is elsewhere, such as in Sql Server, you may be better suited in the long run using a different display technology.
That being said, to select a number of dates, as you would do in Access, you can use the Date Add function. If you had a table Processes with a column StartDate, you could use the query
SELECT *, DateAdd("d",5,StartDate) as "5 Days", DateAdd("d",36,StartDate) as "36 Days"
FROM Processes
to generate a record set to bind your form to. Binding that query to a new form is easy. You just need to change the record source by:
Right click anywhere blank in your new form
Select Properties
Change to the data tab
Click the button next to the text box labeled "Record Source"
Build your query using the built in editor (or, to paste the given SQL, right click in the designer view and select SQL view, then paste)
Close the query building dialog and use your new fields. You can drag them from the field list onto the design surface.