![]() ![]() Try our downloadable Access database demonstration of using Global variables as query parameters. Dim QD As QueryDef Set QD CurrentDb.QueryDefs('Query1') set parameters, start with 0 QD.Parameters(0) 'A' QD.Parameters(1) 'A' QD.Parameters(2) 'A' Dim rs As DAO.Recordset Set rs QD.OpenRecordset if the query is not a select query, use below code QD. We haven’t done any testing but one would assume that if you have 100’s of case statements the lookup of the variable may slow the query down a tad. Is there a downside to using this method – probably. This is our method of choice for all except the simplest of databases. Where Project_ID=Get_Global(‘Project_ID’) Select Project_ID, Project_Name from M_Projects Simple refer to the Get_Global function in the criteria of your query – here’s the SQL: In the query there’s no more trying to figure out the full path to your parameter field which might be buried several sub forms deep or might change during development up or down, requiring the query reference to change. This is easily done by adding the following line of code in the After Update event… In the parameter form that runs the report you save the value selected by the user to the appropriate variable. Public Function get_global(G_name as string) as Variant You might want to do this in you opening form. Note that you’ll need to call this procedure (Get_Global) once when the database opens just to setup the variables. Building Parameter Queries When You Don't Know the Criteria at Design Time You, or your application's users, might not always know the parameters for. The setup is as follows: Create a Module and place the following code into it. It also provides a consistent method throughout your application and a more centralized location for key information. Passing parameters to queries and reports can be a stumbling block for the novice Microsoft. This is perhaps the neatest method and also allows the query to be used for multiple parameter forms, unlike when you reference the parameter form field directly. New! Download Access example of Global Variables The last, less commonly used method is use global variables as query parameters. Reference the form field control that contains the parameter value.īuild the SQL code in visual basic and either run it as a nSQL or create a stored query with the SQL text. Store parameters in a temporary table that is unlinked but defined to the query. Use a criteria entry in the query grid to define a parameter that pops up as a question when the query runs. Some are better than others in certain situations, and some are easier than others.Using variables to pass parameters to queries is one of these multi-solution tasks. ![]() įigure 1: A Parameter Query created in the Query Design Grid.Need help with Global Variables? Your time is too valuable – call us and we will solve the problem or there is no charge! $100 1/2 hour.Īfter reviewing our example: all about global variables you are ready to put this knowledge to good use using global variables to pass parameters to a query.As with nearly all tasks in Microsoft Access there are usually four or five different ways to a solution. As you may remember, this has to be enclosed within square brackets.
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