I have a db in Access and I'm trying to get a textbox to run my query and pass an other bounded textbox's value in as the criteria in DLookUp. I have the query running in design view and when I enter the criteria directly it returns the correct results. When I open the report it gives me the sum of all the possible rows. In other words it doesn't filter the rows.
I haven't used Access in about twelve years, thankfully, and everything I've done up to this point has been tutorial/example patchwork, but here it is...
SQL Query:
SELECT Sum(IIf(Attended=-1,1,0)) AS attendance
FROM Students_Classes_Attendance
WHERE (((CStr([Students_Classes_Attendance].[Class_Id]))=[classId]));
DLookUp as Control Source:
=DLookUp("[Total Attendance by Class]![attendance]",
"[Total Attendance by Class]",
"[Class_Id] =" & [Class_Id])
I'm lost at the moment. I'm guessing that the value isn't there before the query fires and since the criteria is an optional parameter that it's being passed null, but I would hope you'd get an error from that. Not that #Error is very meaningful anyway.
Does anyone know for certain the problem and the best way to correct it? Thanks.
Edit:
I did the changes recommended in the answer so now my DLookUp looks like...
=DLookUp("[attendance]",
"[Total Attendance by Class]",
"[Class_Id] =" & [Class_Id])
...still returns the total for all rows. Removing the criteria completely makes no difference either, which returns me to thinking it has something to do with the bound textbox not having a value.
DLookup uses the following syntax:
Syntax for numerical values:
DLookup("FieldName" , "TableName" , "Criteria = n")
Syntax for strings: (note the single apostrophe before and after the string value)
DLookup("FieldName" , "TableName" , "Criteria= 'string'")
Syntax for dates: (note the # before and after the date value)
DLookup("FieldName" , "TableName" , "Criteria= #date#")
I believe you just need to remove the table name from the first parameter. Try this:
=DLookUp("[attendance]", "[Total Attendance by Class]", "[Class_Id] = " & [Class_Id])
Keep in mind that if Class_Id is a Text Field, you need to surround it by single quotes:
=DLookUp("[attendance]", "[Total Attendance by Class]", "[Class_Id] = '" & [Class_Id] & "'")
Related
Access 2013 - Reference an Unbound text box on a Form
I am currently trying to use an unbound text box [Text161] on a Form name [DCM_Gap_Servers] to sort information through a table. I want the query that I created to be able to take the users input from [DCM_Gap_Servers]![Text161] as the field that is being sorted from the table names 'Server'.
This is the SQL I am using right now in the query:
SELECT * FROM Servers WHERE "Forms![DCM_Gap_Servers]![Text161]" IS NULL
** I have already Tried:
"Forms![DCM_Gap_Servers]![Text161]" ; (Forms![DCM_Gap_Servers]![Text161]); Forms.[DCM_Gap_Servers]![Text161]
This will work at any time if I replace the Text Box reference with the actual Field name I am using, but since there are hundreds of combinations of fields, I need the reference to work.
I have looked all over, and I can't seem to find the correct answer. I am willing to do it in VBA if needed, whatever it takes to get the filtering done correctly.
Thank You.
It is:
SELECT * FROM Servers WHERE Forms.[DCM_Gap_Servers].[Text161] IS NULL
but that will just select all records whenever your textbox is Null.
So it rather is:
SELECT * FROM Servers WHERE SomeField = Forms.[DCM_Gap_Servers].[Text161]
To use the form value as a field name, you must use concatenated SQL:
strSQL = "SELECT * FROM Servers WHERE " & Forms![DCM_Gap_Servers]![Text161].Value & " IS NULL"
This you might pass to the SQL property of an existing query object:
MyQueryDef.SQL = strSQL
Or:
Constant SQL As String = "SELECT * FROM Servers WHERE {0} IS NULL"
FieldName = Forms![DCM_Gap_Servers]![Text161].Value
MyQueryDef.SQL = Replace(strSQL, "{0}", FieldName)
Of course, take care the the field name isn't a zero length string.
I have three date columns. My report has 6 parameters: start and end date range for all three columns. Currently user has to select all date range but what if I want to allow user to only select one date range at a time. I cannot do "allow NULL values" option in the parameter because that see it as a field containing null value. I don't think it's possible to allow user to select only one parameter at a time so I'm trying an approach where there will be three parameters: one will consists of date field names. And rest two are based on date range of the field that is select from previous parameter. For example user selects a date field name from first and then date parameters will be cascaded and grab a value of date field based on the date field name that is selected in previous parameter. But I'm not sure exactly how to approach this. Any ideas?
I do that in some of my reports. The first parameter is "Does the range apply to A, B, or C" and the second and third parameters are the start and end data respectively. Well, I use integers, but dates should work the same as long as you format them.
The way it works, is you set the query in your dataset to be a function, and build it as mostly a quote but with the parameter values substituted in. A typical one might be
= "SELECT * FROM dbo.Trips WHERE " + Parameters!WhatField.Value + " between '" + FormatDateTime(Parameters!StartDate.Value, dateformat.shortdate) + "' and '" + FormatDateTime(Parameters!EndDate.Value, dateformat.shortdate) + "'"
Your parameter "WhatField" is a drop down list with 3 permitted values, make the value be the field name and the display be what your user wants to see as a description of the field.
I think you have to set the query for delayed evaluation somewhere (but I can't spot where right now, so maybe I'm mis-remembering), and you should set default values for your parameters that don't crash your report, but other than that it's fairly straightforward.
Oh, and to make the query a function it's just like a text query but hit the button to the right of the text box - it has a "fx" on it
If you need an even more complex query, you can put the whole query text in code (off the report properties) and call that function from the "fx" button to generate your query string.
Sorry if the title is confusing. But I have a table with a few different columns. One column is the KitNumber and the other is the ReturnDate. I am trying to select the value of the ReturnDate to see what the length of the entry is (also, does VBA let you get the length of a date?). What I need to do though, is the user will enter a number in an unbound, and then that value will look in the table to see if it matches another value in there, and if it does, it will select the return date. Here is the code I have now:
strSQL = "SELECT ReturnDate FROM Crew WHERE KitNumber = " & Me.AssignKit
Debug.Print strSQL
DateLen = Len(strSQL)
So say I enter '111111' in the unbound. I want it to look in the table then to see if there is a matching number. Then if there is it should return the ReturnDate value and get the length of it. Cause right now the Debug just returns the KitNumber instead of the date. Anyone be able to help me out? Thank you
If it's a one off, then a DLookup in the OnExit or OnChange events should give you the info you need to work with
using your example,
Debug.Print DLookup("ReturnDate","Crew","KitNumber = " & Me.AssignKit)
if KitNumber is stored as a string in the database, then you would need to put quotes around the selection
Debug.Print DLookup("ReturnDate","Crew","KitNumber = '" & Me.AssignKit & "'")
Note that DLookup returns the first one it finds, so if you need multiple values, you will have to look into recordset functions .Find and .FindNext
I have a problem very similar to this one, but I just can't seem to solve it!
In MS Access (2003), I want to search a table based on entries in a number of fields, some of which may be empty.
I have:
text fields
date fields
integer fields, and
a memo field (but we can probably not bother searching this one if it is difficult).
They map onto a table exactly.
I am trying to create a query that will return matching rows when data is entered into one or more of these fields, but some fields can be left blank. How the heck do I do this?
A query like the one on the linked question works for text fields, but what do I do about the number fields, date fields (and possibly even the memo field)?
To give a clear example, the following code block works for TextField1, but not NumberField1:
PARAMETERS [Forms]![SearchForm]![FilterTextField1] Text ( 255 ), [Forms]![SearchForm]![FilterNumberField1] Text ( 255 );
SELECT Table1.[TextField1], Table1.[NumberField1], Table1.[TextField2], Table1.[TextField3], Table1.[DateField1], Table1.[DateField2], Table1.[DateField3]
FROM Table1
WHERE (Len([Forms]![SearchForm]![FilterTextField1] & '')=0 OR Table1.[TextField1] Like '*' & [Forms]![SearchForm]![FilterTextField1] & '*') AND (Len([Forms]![SearchForm]![FilterNumberField1] & '')=0 OR Table1.[NumberField1] Like '*' & [Forms]![SearchForm]![FilterNumberField1] & '*');
I do hope you can help. I'm sure I'm missing something really obvious, but for some reason my brain feels like it is leaking out of my ears at the moment.
Thank you!
If you need it, this is the basic design of the relevant entities:
Table1
SomePrimaryKeyWeDontCareAboutRightNow
TextField1
TextField2
TextField3
NumberField1
DateField1
DateField2
DateField3
MemoField1
SearchForm
FilterTextField1
FilterTextField2
FilterTextField3
FilterNumberField1
FilterDateField1
FilterDateField2
FilterDateField3
FilterMemoField1
You can check fo null values or cast to string
You could certainly spend a great deal of time crafting a huge and very hard to debug SQL query for this, or just jump into VBA and write some code to construct just the SQL you need.
VBA is there just for these kinds of scenario, where something is either impossible or becoming too complex to do otherwise.
With VBA, you can use an initial SELECT query that collect all the data, and then construct a WHERE clause based on the content of your search form to filter it.
For instance, I have a form like this, that allows the user to enter any criteria to filter a list of prices:
Some code to implement this could look like:
' Call this whenever the use click the Apply button '
Private Sub btApply_Click()
' Construct the filter '
Dim filter As String
If Not IsBlank(cbSupplierID) Then
If Not IsBlank(filter) Then filter = filter & " AND "
filter = filter & "(SupplierID=" & cbSupplierID & ")"
End If
If Not IsBlank(txtPartNumber) Then
If Not IsBlank(filter) Then filter = filter & " AND "
filter = filter & "(PartNumber LIKE '*" & txtPartNumber & "*')"
End If
If Not ckShowLocked Then
If Not IsBlank(filter) Then filter = filter & " AND "
filter = filter & "(NOT PriceLocked)"
End If
' ... code snipped, you get the jest ... '
' Now re-construct the SQL query '
Dim sql As String
sql = "SELECT * FROM Price"
If Not IsBlank(filter) Then
sql = sql & " WHERE " & filter
End If
SubForm.Form.RecordSource = sql
End Sub
It may seem like a lot of code, but each block only does one thing, and it's a lot easier to debug and maintain than cramming everything into a query.
I'm trying to count the number of records in a table that meet a certain criteria. My preference is to use SQL, not Dcount, as I want to get better at SQL. Here's my current code below:
Dim countString As String
Dim count
countString = "SELECT COUNT(*) FROM `Engagement Letters` WHERE 'Client ID' = " & Me.cboSelectClient
count = CurrentDb.OpenRecordset(countString).Fields(0).Value
Yeah I know, I've used spaces in my tables and field names - I will change that. Though I think I should still be able to run this query as is, so I will leave it as is for now.
When I run the above, I get runtime error 3464 - data type mismatch in criteria expression. I've had the below dcount function work fine:
count = DCount("[Engagement Letter ID]", "Engagement Letters", "[Client ID] = " & Me.cboSelectClient)
And also the below COUNT query without the WHERE works fine:
"SELECT COUNT(*) FROM `Engagement Letters`"
My knowledge of SQL is very minimal, and my knowledge of more advanced VBA is also quite minimal, so I'm not sure where I'm going wrong. Can anyone help me with this?
Try building your string like this.
countString = "SELECT COUNT(*) FROM [Engagement Letters]" & vbCrLf & _
"WHERE [Client ID] = " & Me.cboSelectClient
Debug.Print countString
Use square brackets around object (table and field) names which include spaces or any characters other than letters, digits, and the underscore character.
For the table name, you used `Engagement Letters`, and the backticks appear to work the same as square brackets. Perhaps they always work equally well, but I don't know for sure because I use the brackets exclusively. And brackets instead of backticks might help you avoid this mistake ...
WHERE 'Client ID' = " & Me.cboSelectClient
... that was asking the db engine to compare the literal string, "Client ID", to the numerical value (?) you pulled from cboSelectClient.
I used vbCrLf between the 2 parts of the SELECT statement because I find that convenient when examining the completed string (via Debug.Print).