Modules & VBA :: How Can Function Return Multiple Values And Not Re-run In Query
Jan 11, 2014
Trying to run a query where each 4 fields calling a custom function will not just re-run the same custom function over and over again for each field in a single record.
A Function has a huge amount of multiple queries and logic to perform.The Function returns a Integer, Integer, Integer, and optional Integer. Each integer requires a DLookup to lookup a String description value for each individual integer (in each of 4 fields).
The problem is, the DLookup in each column that runs against each of the integers re-run the same function.The result is that a single record, each of the 4 columns returning a single of the 4 values, the complex function is re-run 4 times.
The function is huge, part of a Business Rules Engine. Depending on the Rule-Meta data - it might launch up to a dozen queries and perform logic steps for each record. This is not the ordinary SQL Query.
Imagine if one record (for 1 field) takes 0.1 second to run. By referencing the function in 4 columns, this same function is re-run 4 times (0.4 Seconds) Against 50,000 records - this duplication of re-running the function for each column can really add up.
Possible Solutions: Researched Class Modules - There is a comment that the property Get, Let actually reduce performance. There are huge advantage of code documentation, documentation and centralization.It doesn't claim class modules reduce execution as each propery is returned. It also describes that Class Modules can't be called directly in a Query - unless each property is wrapped in a function.
Function Returns one String with delimiters: e.g 34;54;55;1 This single column goes into a Make Table (runs function one time per record) Then the D-Lookup is run against static local data. This pevented the function from being run over and over across the network linked data.
Final Solution: Eventually, the many hundred lines of VBA code for the Rules Engine will be converted into SQL Server T-SQL Functions on the server.For a Rule Engine development, Access has been great for a rapid protoype development and testing. The TSQL will be a final big step requiring re-coding. It is not currenty my option for the delivery time frame.
I have two date fields in a table. I need to find the days between these dates and, if its greater than 7 days, I want to display the record in a report, so far, I have found a hand function that allows me to enter two dates and it returns a long data value representing the number of days in between the two dates. (google "I've developed the following code to count the business days between 2 dates." and its the second one that starts as SOLVED I made no mods to it as it does what i need it to do.
So, i added this to its own module within the data base for use within a query. My test query basically displays the unique ID, the start date and the end date and then displays the values returned from the function. here is the SQL:
SELECT [Main Table].[Unique ID], [Main Table].[Start date], [Main Table].[End Date], (Business_Days_Between([End Date],[Start date])) AS [Days between] FROM [Main Table] WHERE ((([Main Table].[Start date]) Is Not Null) AND (([Main Table].[End Date]) Is Not Null));
When ran, this Query works... However, when I enter a criteria like =2 or > 7, it says data type mismatch. I have even attempted the CInt() function to make sure its formated as int but i continue to get the same error.
I can not seem to work this out in a single query.
I have: tblChildren tblParents tblGuardians
Because so many familes that use day care are fractured, it is possible for 1 parent to have multiple kids but some of them to have a different second parent.
Therefore each parent and each guardian has thier own line and own unique ID in their respective tables.
each child in tblChildren can have up to two Parent IDs (Parent_ID_1 & Parent_ID_2) and up to two Guardian IDs (Guardian_ID_1 & Guardian_ID_2) I've set the data entry form to require at least one parent for each child, but there may not be any 2nd parent or any guardians.
So what I now need to do is create a query, or series of queries, that results with each child on it's own line, with the name of each parent, and each guardian in thier respective fields.
I would like to select a case depending on the output of a function.
This function tests the syntax of the reporting month.
If the syntax is fine nothing should be done further in the main sub else it should return to the Input window for the reporting month.
Somehow it doesn't work out.
Code: Public Function RepMonthCheck(rep_date As String) as Boolean If Len(rep_date) <> 6 Or Left(rep_date, 2) > 12 Or Left(rep_date, 2) < 1 Then MsgBox ("Reporting rep_date is not in the correct format = mmyyyy") Return False ElseIf Right(rep_date, 4) > 9998 Then MsgBox ("No forecast available for year 9998")
Question for Documentation purpose: Should the Public Type be declared in its own module?
Or should it be declared in a standard module where non-public functions use it? It is not for a Form module use.
For a Rule Engine, a function is calling one record on 4 different SQL Views (as linked tables) that have the same field format.
For speed, the recordset should only be opened once. However, there are multiple values that must be returned to the result table multiple fields.
One way to return multiple values is an Array. That has over head too.
Another way is to create multiple public variables. Not my choice for documentation. Another is to create a string.
This is a pure code module with several non public functions / subs. What is the documentation preference? List a Public Type close to the function, or place it in the Global module?
Background: A function can only have one return value.
By creating a public Type, multiple values can be returned.
Code: Public Type Income Wages As Currency Dividends As Currency Other As Currency Total As Currency End Type
Use this structure as the return type for a function. In a real situation, the function would look up your database tables to get the values, but the return values would be assigned like this:
Code: Function GetIncome() As Income GetIncome.Wages = 950 GetIncome.Dividends = 570 GetIncome.Other = 52 GetIncome.Total = GetIncome.Wages + GetIncome.Dividends + GetIncome.Other End Function
To use the function, you could type into the Immediate Window:
GetIncome().Wages
(Note: the use of "Public" in the Type declaration gives it sufficient scope.)
Important Notice The way this function is called will work, but is wrong from the aspect it re-calls the recordset over and over.
Need to use CAST to return integer value of string (digits as data type string).
Where clause looks like this:
... Where Cast([Price File] as int) > 0
works fine in SQL Server but not sure what syntax is in VBA . Using Paul Baldy's suggestion to set Select statement as string and do the debug.print to verify that SQL has no goofs ... looks good but not to Access. What is proper syntax?
I have a subformClientOffers on my frmAllProperties. On the subformClientOffers is a field called Outside Agents. This field allows for multiple values to be selected.
The subfrmClientOffers is in datasheet view.
While the field Outside Agents DOES allow me to select more than one, they post in the field one after another:
Ken Shaw, John Doe, Jane Doe, Harlan Bestlyn
Therefore, the datasheet view of the subformClientOffers causes the field Outside Agents to get very long, much too long to view without scrolling. My client wishes for everything on the frmAllProperties to be viewable without scrolling.
Is there anyway, to cause the field Outside Agents to place a return between each selected name (sort of a wrap text kind of thing)?
One thing I might mention is that the field is a drop down field from tblOutsideAgents. The table itself has First Name and Last Name, but I concatenated that into Fullname on the form, so that when the user opens the drop down they see the entire name. I don't know if that would have any effect on making the 'return' thing work or not.
I can't use this field as a subdatasheet because I already have one subdatasheet attached to the subform to show multiple notes on each Client Offer.
The code has fixed path information on a lot of places in different SQLs (DoCmd.RunSqL command). I want to replace fixed path info with variable path info. Variable path info is stored in the table.
I managed to achieve that in the following manner:
Code: Dim db As Database Dim dbName as String Set db = CurrentDb Set rs = db.OpenRecordset ("TableName", dbOpendynaset) rs.FindFirst ("ID = " & 2)
[Code] ....
where I would use as variable Function name instead of dbName.
How to make module that will enable to use Function name as variable path information for SQL queries?
I have a simple UDF that takes a string and returns a variant, which is an array of strings Example Input "Brick Wall" Return value would be a variant array with first element "Brick" and and second element "Wall" Now I have a table with a field of strings, and I want to make a query that returns all the results from the function, one per line.
So if my input table looks like this
[strField] "kick the ball" "return the pass"
my query result should looks like this
[Orig] [new] "kick the ball" "kick" "kick the ball" "the" "kick the ball" "ball" "return the pass" "return" "return the pass" "the" "return the pass" "pass"
Last time I had to do something like this I used VBA exclusively, with ADO objects, but I thought a query based solution would be easier.
With my current data the largest return array size my function returns is 27 elements but I wouldn't want to rely on that number being fixed.
I have a query that uses a linked table from an external database and joins it with a table from my database to return records that contain the same values.
Is there a way to return only the records that are present in the external database and not in my db?
I need an Access query to return the rate at which a customer should be charged. A customer's rate can be set for a period of 1 to 6 months and the customer's rate table could look like this:
I have two tables: tblStudents and tblEnrollments. The query I have designed shows the StudentID and counts the number of Enrollments that each student has. I want the students who don't have any enrollments to still show up and have a 0 by their ID. Right now, only the students with enrollments show up in the query results.
Here is my SQL Statement:
SELECT tblStudents.StudentID, Count(tblEnrollments.EnrollmentID) AS CountOfEnrollmentID FROM tblStudents INNER JOIN tblEnrollments ON tblStudents.StudentID = tblEnrollments.StudentID GROUP BY tblStudents.StudentID;
What do I need to do to it to have null values display as zero?
I have been trying to find a solution to why I can't get a Dlookup with multiple criteria to return the value I need.
Essentially I am trying to use an Order Number to find the item number which is contained within another table. However the order number has multiple lines (suffixes) which alter the item number. Therefore I am trying to have the item number be populated by the correct 'combination' of Order Number and line ("suffix").
I have managed to use the Dlookup in the after update of each box of the form separately and they retrieve values in the table correctly:
Afterupdate of main order number:
Code:
Private Sub OrderNumbertxt_AfterUpdate() ItemNumbertxt = DLookup("item", "dbo_job", "[job] = '" & Forms![**INPUT]![OrderNumbertxt] & "'") End Sub
Afterupdate of suffix:
Code:
Private Sub SuffixTxt_AfterUpdate() ItemNumbertxt = DLookup("item", "dbo_job", "[suffix] = Forms![**INPUT]![SuffixTxt]") End Sub
However when I combine them as follows in the afterupdate of the Suffix box I receive a "Run-time error '13': Type mismatch"
Code:
Private Sub SuffixTxt_AfterUpdate() ItemNumbertxt = DLookup("item", "dbo_job", ("[suffix] = Forms![**INPUT]![SuffixTxt]") And ("[job] = '" & Forms![**INPUT]![OrderNumbertxt] & "'")) End Sub
I think the reason is something to do with some being numbers and some being a combination of text and numbers (based on the replies of other topics), but have been trying to modify these slightly and can't get it to work still.
Also the Order Number is a combination of letters and numbers (normally in the form of AB12345678), the suffix is just a number between 0-9 and the Item number it finds is a combination of numbers and letters.
I'm trying to create a report that's based on a query, and the query has three fields: [PersonName], [PersonDate], [PersonShift]. This table holds records for people that worked on certain days and certain shifts. What I want to do is create a report that gives a graphical calendar display of each day in a month, and on any day that the person has a record (and sometimes there are more than one), I'd like to see just the PersonShift records showing in that day's box.
tblPersons PersonName PersonDate PersonShift Jason 4/10/14 FIRST Jason 4/13/14 FIRST Jason 4/13/14 SECOND
So if I were to print this report for Jason, I'd get all the days in April laid out like a calendar, and on 4/10/14 you'd see "FIRST" in the box, and on 4/13/14. you'd see FIRST and SECOND in the box. All the other boxes would be blank.how to display the calendar, how to display the dates. I'm able to return records to those boxes by creating 31 separate queries, one for each day of the month, and each query returns records for that day. The queries are added to the report as subreports. It all works beautifully.
The thing is, I'm running 31 queries every time I pull the report. Is there a way to code a single field on a report that will run a SELECT statement on the table using variables that are located in fields elsewhere in the record?
If I have a PersonName field on the header of the report, and I have a PersonDate field in the detail of the report's record, can I create a new field in the detail of that record that runs a SELECT statement on qryPersons, and filters the tblPersons by the PersonName on the header of the report and on PersonDate in the record?
I want a field on a report that runs a SELECT statement on tblPersons, I want the field to return only the PersonShift records for that person based upon the PersonDate. Each of the fields on my report have a CalendarDate field, and I want the SELECT statement to return records where the PersonDate matches the CalendarDate, and again, it should only display PersonShift records.
I have a table that has a list of tasks and checkboxes attached to them to be checked once the task is completed. I need to run a query on the table that will only bring me back the tasks with a completion that is false.
Everything that I read online indicates that this is a difficult task for access. Maybe I can accomplish this in SQL view instead of design? If I put false is all of the yes/no fields, the query brings back nothing.
I have a set of devices that are assigned to a truck, on occastion they are moved from truck to truck, I need to be able to track where they are AND where they have been. Here is what I have:
ID (autonumber) GPS ID (number, this is the specific ID to each device) Truck Number (this is the specific ID for each truck Installation Date (Date installed / moved)
I have created a query to show the data I need, I have put them in order based on date.
- I must keep each event stored on the table
Goal:
To show a list of the current location of each device, nothing more.
I've created an array that I created and declared as a Public array in my module. I created a function that populates the array so that I can use the values in another function. I've gotten the array to populate but when I go to use the values in the array in another function, the array appears at Empty. I seem to be stuck on declaring it properly or something so that it can be used by other functions.
Public arrWebIDs As String Public Function FillArray()
I have a form with couple of textboxes bound to a table. When the user opens the form to enter records, i want to write a function that would go through the textboxes to check whether the textboxes are left NULL. Now i can write code on button click for each form, but i was wondering if its possible to write a function that could be called for each form that i have to check for null values.
I made a custom function to look certain value from table based on couple of criteria that it gets from query where I want to use it. Function's code is below:
Code: Public Function PotteryWeights(strLocusID As Long, nrPotSubID As Long) As Variant Dim priSubID As Long Dim priLocusID As Long Dim priResult As Variant priSubID = nrPotSubID
[Code] ...
However, when I use it in query it only returns Case else - option and everything else is empty.
I have a query that runs off three tables: These are tbl_contacts, tbl_status, tbl_publications. All contacts have a status but not all will have a publication. The problem is that when i run the query on a status type where none of the contacts for that status have a publication it will return no results, where what I actually need is for it to just return the details of those contacts for that status. The whole query runs off a form with combo boxes.
when I open my Quotations form I'd like a set of services to be selected by default, ex: Brush and Pen. So the user only has to input the quote amount
is there anyway to have the form open with a script like: "on open (or on load). in subform SELECT refproduct where product from tblproducts = 1 and also SELECT refproduct where product from tblproducts = 4" Therefore when my main form opens, in the subform I have already Brush on the 1st line selected and pen on the 2nd. My user only has to type the price.
I have already made a query with all the information needed. What I am trying to do is create a form where a user can open the database and enter a unique number and have information from 10 fields associated with that number show.
I have a database with various tables containing information about students, timetabling, assignment submission dates and multiple tables with grades for various assessments. All grades are held as percentages.
In a large number of different queries / reports I want to output the grade as an item from verbose scale with 17 points (excellent first, high first etc.). I've set up a table called 17pointscale which contains fields called 17pointscale (with the verbose names), lowerlimit (number) and upperlimit (number).
I have a query in SQL (which works) to take the percentage grade from one of my grade tables AssessedWorkGrades.Grade and return the text on the 17 point scale.
SELECT AssessedWorkGrades.Grade, [17PointScale].[17PointScale] FROM AssessedWorkGrades LEFT JOIN 17PointScale ON ([AssessedWorkGrades].[Grade] >= [17PointScale].[LowerLimit]) AND ([AssessedWorkGrades].[Grade] <= [17PointScale].[UpperLimit]);
Is there any way of converting the SQL to a custom vba function which would enable me to use this as a lookup in a large number of queries.
I think that it should be possible to set up a function called ScaleGrade and in any query Expression: ScaleGrade(XXX) will take XXX and return the 17 point scale.
I think that AssessedWorkGrades.Grade needs to be replaced by a variable that is inputted on use of the function but am not sure how to accomplish this.
I am trying to write a query that will return records from multiple tables. I currently get an error suggesting I create a subquery or else I get far too many records.
The query is EditAttendanceQuery (I left it in a bit of a state). The fields I need are shown in the query. The records I need are based on the Edit AttendanceQuery (Form). I can get the records I need without the CourseNumber and Section, but it all goes downhill when I include them.
I have multiple reports that use similar IIF statements as the controlsource for four textboxes. Naturally, I don't want to have to update twelve controlsources if any of the calculations change, so I thought I'd make this a public function. However, I don't know how to pass along multiple textboxes as variables. Here's what I have so far:
Code: Option Compare Database Public Function txtColor(ByRef textbox As Control) Dim str1, str2, str3, str4 As String 'The IIf statement is simplified for this example. It's not important. str1 = "=IIf(IsNull([Inquiry start date]),'W',IIf([txtInquiry]<1 And IsNull([Inquiry end date]),'R'))"
[Code] ....
And this is in the report (where ??? is what I'm asking about)
Code: Private Sub Report_Load() Call txtColor(???) End Sub
