Simple access query - ms-access

I'm trying to create a query in Access.
Let's say, for example, I have four fields: Numbers 1-26, Letters A-Z, 26 Names, and 26 Cities, so one record might be: 2, B, Jane, New York
I want to create and save a new query with:
the numbers field, the letters field, and the names field. I want the letters field to be filtered on "A" or "B", and the names field to have an expression so it's always 0.
This will become a loop, so it'll create 13 queries (A/B, C/D, etc).
It seems like having this process in VBA as opposed to the Access macro builder would be better since not only do I have to loop this process, but there are also 2 similar tables (same field names, different values) that I need to run it on.

You can run your queries in VBA using a recordset and then work with the data from there:
Sub YourQueries(ByVal pstrCol1 As String, ByVal pstrCol2 As String, ByVal pstrCol3 As String, ByVal pstrCol4 As String)
Dim rs As Recordset
Dim strSQL As String
' Change types above to match what's actually in the table
strSQL = "SELECT YourColumn1, YourColumn2, YourColumn3, YourColumn4 "
strSQL = strSQL & " WHERE "
strSQL = strSQL & "YourColumn1='" & pstrCol1 & "'"
strSQL = strSQL & " AND YourColumn1='" & pstrCol1 & "'"
strSQL = strSQL & " AND YourColumn1='" & pstrCol1 & "'"
strSQL = strSQL & " AND YourColumn1='" & pstrCol1 & "'"
Set rs = CurrentDb.OpenRecordset(strSQL, dbOpenSnapshot)
While Not rs.EOF
For i = 0 To 3
Debug.Print rs.Fields(i) & " is Column" & Format(i)
Next i
rs.MoveNext
Wend
rs.Close
Set rs = Nothing
End Sub

Related

Cannot use ListBox values in MS Access 2007 to pass to query

Good morning,
I am helping to develop an interface via a Form in MS Access. We have a list box with various user values and the user should be able to select multiple values in the ListBox and then press the button to execute a query, returning only the rows whose Car Name is what was selected.
UPDATE - thanks to some great feedback on this forum, the primary issue was resolved. My secondary issue is now not being able to execute the query. When I try, I get the error that the query cannot be executed.
My code (as event procedure) for the button is:
Option Explicit
Private Sub btnSearchCars_Click()
MsgBox "Starting Sub"
Call QueryCars.myQuery
MsgBox "Ending Sub"
End Sub
Then, my QueryCars module looks like this:
Sub myQuery()
Dim strWhere As String
Dim strSQL As String
Dim varItem As Variant
For Each varItem in Forms!FormSelect!listCarID.SelectedItems
strWhere = strWhere & "'" & Forms!FormSelect!listCarID.ItemData(varItem) & "',"
Next
strWhere = Left(strWhere, Len(strWhere) -1)
strSQL = "SELECT tblBig.* FROM tblCars INNER JOIN tblBig ON tblCars.Car_ID = tblBig.Car_ID WHERE tblCars.Car_ID IN (" & strWhere & ");"
DoCmd.RunSQL strSQL
End Sub
My error is an "A RunSQL requires an argument of an SQL statement" error on the line.
DoCmd.RunSQL strSQL
I would really appreciate it if someone could help. All I am trying to do is take the values from the list box the user selects and use them as WHERE criteria in my query. I have searched various SO and Access forums all morning and have not found anything to help.
Thank you. Please let me know if you have any questions.
This isn't the perfect answer I was hoping to give you - but can't figure out how to use parameter queries in an IN command.
I'll assume that your listbox contains two columns of data and the CarID values are in the first column.
The main function is called ProcessQuery and accepts a reference to the listbox as an argument:
Public Sub ProcessQuery(myList As ListBox)
You can then call your code from the event on the listbox and pass it the listbox reference.
Private Sub btnSearchCars_Click()
ProcessQuery Me.listCarID
End Sub
The ProcessQuery procedure then looks at the first column to get the index numbers, constructs the SQL, opens the resulting recordset and pulls the info from each record.
Public Sub ProcessQuery(myList As ListBox)
Dim vItem As Variant
Dim IDList As String
Dim qdf As dao.QueryDef
Dim rst As dao.Recordset
For Each vItem In myList.ItemsSelected
'Column 0 is first column in listbox.
IDList = IDList & "'" & myList.Column(0, vItem) & "',"
Next vItem
'Removes the final ,
IDList = Left(IDList, Len(IDList) - 1)
'Create a temporary query definition & open the recordset.
Set qdf = CurrentDb.CreateQueryDef("", _
"SELECT tblBig.* FROM tblCars INNER JOIN tblBig ON tblCars.Car_ID = tblBig.Car_ID WHERE tblCars.Car_ID IN (" & IDList & ")")
Set rst = qdf.OpenRecordset
'Move through the recordset and output the first two fields from each record
'to the Immediate window.
With rst
If Not (.BOF And .EOF) Then
.MoveFirst
Do While Not .EOF
Debug.Print .Fields(0) & " - " & .Fields(1)
.MoveNext
Loop
End If
End With
End Sub
To display the query result as a datasheet you could use the following, but I'd prefer to use a stored query with a parameter for the IN. I'll try and figure that bit out.
Public Sub ProcessQuery(myList As ListBox)
Dim vItem As Variant
Dim IDList As String
Dim qdf As dao.QueryDef
Dim rst As dao.Recordset
For Each vItem In myList.ItemsSelected
'Column 0 is first column in listbox.
IDList = IDList & "'" & myList.Column(0, vItem) & "',"
Next vItem
'Removes the final ,
IDList = Left(IDList, Len(IDList) - 1)
'Create a temporary query definition & open the recordset.
Set qdf = CurrentDb.CreateQueryDef("TempQDF", _
"SELECT tblBig.* FROM tblCars INNER JOIN tblBig ON tblCars.Car_ID = tblBig.Car_ID WHERE tblCars.Car_ID IN (" & IDList & ")")
DoCmd.OpenQuery "TempQDF", acViewNormal
End Sub
I would suggest first taking a look at the actual WHERE clause being generated...keep a separate string variable to store it, and then dump it to the Immediate Window when it's generated.
I would also suggest creating a separate function to return values selected in a list box as an array. Something like:
Public Function getListBoxSelection(ctl As Access.ListBox) As Variant
Dim arr() As Variant
Dim varItem As Variant, i As Long
If ctl.ItemsSelected.Count > 0 Then
ReDim arr(0 To ctl.ItemsSelected.Count - 1)
i = 0
For Each varItem In ctl.ItemsSelected
arr(i) = ctl.ItemData(varItem)
i = i + 1
Next varItem
End If
getListBoxSelection = arr
End Function
Then, you would call it in SQL generation. Something like
whereClause = join(getListBoxSelection(me.listCarID), " AND ")
debug.Print whereClause
qdf.SQL = _
"select tblBig.* " & _
"from tblCars " & _
"inner join tblBig on tblCars.Cat_ID = tblBig.Car_ID " & _
"where tblCars.Card_ID in (" & whereClause & ")"

VB6, MS Access, DAO - Display all records WHERE column-name IS NOT NULL

I need a bit of help with this, so what I am trying to do is to display all records WHERE column-name IS NOT NULL. What I have is:
Dim rs As Recordset
Dim sqlStr As String
Set WS = DBEngine.Workspaces(0)
DbFile = (App.Path & "\mydb.mdb")
strSql = "SELECT * FROM MyDatabaseName"
Set rs = db.OpenRecordset(strSql)
rs.MoveFirst
Do While Not rs.EOF
lblResult.Caption = ("cust Name: " & rs!SurName & " cust Surname: " & rs!FirstName)
rs.MoveNext
Loop
MsgBox ("End ")
What I have tried is
strSql = "SELECT * FROM MyDatabaseName WHERE column-name IS NOT NULL"
But I get an error 3131. Any help is appreciated. Also how can I display the result in a ListBox insted of Label.
Simple fix: enclose column names in square brackets when using special characters, like the - substraction operator:
strSql = "SELECT * FROM MyDatabaseName WHERE [column-name] IS NOT NULL"
The rest of your SQL seems valid.
If you want a list box with the results of this query as the list, just set its row source equal to this query, and set its row source type equal to Table/Query. No need for any VBA.
If you want to put everything in a label, use:
Do While Not rs.EOF
lblResult.Caption = lblResult.Caption & "cust Name: " & rs!SurName & " cust Surname: " & rs!FirstName & VbCrLf
rs.MoveNext
Loop

SELECT Queries in Access VBA

I have an Access database consisting of two tables, Individuals & Pairs. Individuals consists two columns; 'Bird_ID' and 'Parents_Pair_number' and Pairs consists of three columns; 'Pair', 'Female_ID' and 'Male_ID'. 'Parents_Pair_number' and 'Pair' have a Many-to-one relationship. Via this relation one can check the parents of an individual.
But now I was thinking of making automatized family trees using a form. My plan was to make a field (Bird_ID_Field) in which you can find a certain individual and that other fields such as Father, Mother, Fathers father etc. etc. would auto-fill based on that entry.
I tried to auto-fill the Father_ID (Field) using the following VBA code:
Dim strSQL As String
Dim strBird_ID As String
If Bird_ID_Field <> "" Then
strBird_ID = Bird_ID_Field
strSQL = "SELECT Pairs.[Male_ID] " & _
"FROM Pairs " & _
"WHERE PAIR = (SELECT Individuals.[Parents_Pair_number] FROM Individuals WHERE Individuals.[Bird_ID]= '" & strBird_ID & "');"
DoCmd.OpenQuery strSQL
Father_ID = strSQL
End If
But after updating the Bird_ID_Field I get the following error: Microsoft Access can't find the object ''.
Do you have any idea what's wrong?
Thanks in forward!
Jeroen
You should use recordsets:
Dim rst As Recordset
Dim strSQL As String
If Nz(Bird_ID_Field,"") <> "" Then
strBird_ID = Nz(Bird_ID_Field, "")
strSQL = "SELECT Pairs.[Male_ID] " & _
"FROM Pairs " & _
"WHERE PAIR = (SELECT Individuals.[Parents_Pair_number] FROM Individuals WHERE Individuals.[Bird_ID]= '" & strBird_ID & "');"
Set rst = CurrentDb.OpenRecordset(strSQL)
If rst.RecordCount > 0 Then
Father_ID = rst![Male_ID]
End If
End If
rst.Close
Set rst = Nothing
And also I would recommend to use JOIN for tables joining instead of subquery.

Display multiple specific records in a report

Let's say I have a single table called "Customers". It contains 2 fields:
Name
Address
I want users to be able to select multiple records by selecting their names. For example something like having a list box containing all the names of the records in the database. I want users to be able to select multiple items like:
Dave Richardson
Bob Smith
Sophie Parker
And then only display records with these names in the report.
You can use the WhereCondition option of the DoCmd.OpenReport Method to filter your report as needed.
Const cstrReport As String = "YourReportNameHere"
Dim custNames As String
Dim lItem As Variant
Dim strWhereCondition As String
With Me.yourListBoxName
For Each lItem In .ItemsSelected
custNames = custNames & ",'" & Replace(.ItemData(lItem), "'", "''") & "'"
Next
End With
If Len(custNames) > 0 Then
custNames = Mid(custNames, 2)
strWhereCondition = "[Name] IN (" & custNames & ")"
End If
DoCmd.OpenReport ReportName:=cstrReport, View:=acViewPreview, _
WhereCondition:=strWhereCondition
Note this approach has features in common with PaulFrancis' answer. In fact, I copied his code and modified it. The key difference is that this approach does not require you to revise a saved query in order to filter the report.
The setup I would I have is, a Form with a SubForm and a ListBox, the Listbox will have the names of all your customers. So the RowSource would be,
SELECT
customerNameFieldName
FROM
yourTableName;
The Multi Select property will be setup to Extended. Then a button will have the following code that will generate the SQL for the SubForm's recordsource.
Private Sub buttonName_Click()
Dim lItem As Varaint, strSQL As String
Dim custNames As String, whereStr As String
Dim dbObj As dao.Database
Dim tmpQryDef As QueryDef
Set dbObj = CurrentDb()
For Each lItem In Me.yourListBoxName.ItemsSelected
custNames = custNames & "'" & Me.yourListBoxName.ItemData(lItem) & "', "
Next
Id Len(custNames) <> 0 Then
custNames = Left(custNames, Len(custNames) - 2)
whereStr = "WHERE customerNameFieldName IN (" & custNames & ")"
End If
strSQL = "SELECT someFields FROM someTable " & whereStr
Set tmpQryDef = dbObj.QueryDefs("Summary 3 Q1")
tmpQryDef.SQL = strSQL
DoCmd.OpenReport "yourReportName", acViewNormal
Set dbObj = Nothing
Set tmpQryDef = Nothing
End Sub
So now the SubForm will have the RecordSource based on all the information you have selected in the ListBox.

Error on a recordset, but same SQL works elsewhere

Error: "Run-time error '3061' Too few parameters. Expected 2.
I wrote this simple function that returns the remaining percentage calculated for number of records changed. It is supposed to occur when the user updates the field called 'percentage' I am certain the code below should work, but obviously something is wrong. It occurs on the line:
Set rs = db.OpenRecordset("SELECT Tier1, [Percentage], Tier3 AS Battalion, Month " _
& "FROM tbl_CustomPercent " _
& "WHERE (((Tier1)=[Forms]![frmEntry]![cmbImport_T1]) AND ((Month)=[Forms]![frmEntry]![cmbMonth]));", dbOpenSnapshot)
I wonder how it could fail when the very same query is what populates the 'record source' for the form with the 'percentage' textbox.
Function RemainingPercentAvailable() As String
Dim db As DAO.Database
Dim rs As DAO.Recordset
Dim strSQL As String
Set db = CurrentDb
Set rs = db.OpenRecordset("SELECT Tier1, [Percentage], Tier3 AS Battalion, Month " _
& "FROM tbl_CustomPercent " _
& "WHERE (((Tier1)=[Forms]![frmEntry]![cmbImport_T1]) AND ((Month)=[Forms]![frmEntry]![cmbMonth]));", dbOpenSnapshot)
Dim CurrentTotal As Single
CurrentTotal = 0
If Not (rs.EOF And rs.BOF) Then
rs.MoveFirst
Do Until rs.EOF = True
CurrentTotal = CurrentTotal + rs!Percentage
rs.MoveNext
Loop
End If
RemainingPercentAvailable = "Remaing available: " & Format(1 - CurrentTotal, "0.000%")
Set rs = Nothing
Set db = Nothing
End Function
Adapt your code to use the SELECT statement with a QueryDef, supply values for the parameters, and then open the recordset from the QueryDef.
Dim db As DAO.Database
Dim qdf As DAO.QueryDef
Dim rs As DAO.Recordset
Dim strSQL As String
strSQL = "SELECT Tier1, [Percentage], Tier3 AS Battalion, [Month] " _
& "FROM tbl_CustomPercent " _
& "WHERE (((Tier1)=[Forms]![frmEntry]![cmbImport_T1]) AND (([Month])=[Forms]![frmEntry]![cmbMonth]));"
Set db = CurrentDb
Set qdf = db.CreateQueryDef(vbNullString, strSQL )
' supply values for the 2 parameters ...
qdf.Parameters(0).Value = Eval(qdf.Parameters(0).Name)
qdf.Parameters(1).Value = Eval(qdf.Parameters(1).Name)
Set rs = qdf.OpenRecordset
Note: Month is a reserved word. Although that name apparently caused no problems before, I enclosed it in square brackets so the db engine can not confuse the field name with the Month function. It may be an unneeded precaution here, but it's difficult to predict exactly when reserved words will create problems. Actually, it's better to avoid them entirely if possible.
This one is calling a query directly in a DAO.Recordset and it works just fine.
Note the same 'Set rs = db.OpenRecordset(strSQL, dbOpenDynaset) This is a parameter SQL as well.
The only difference is with this one is that I DIDN'T need to move through and analyze the recordset - but the error occurs on the 'Set rs = " line, so I wasn't able to get further anyway.
Dim rs As DAO.Recordset
Dim db As DAO.Database
Dim strSQL As String
strSQL = "SELECT Sum(tbl_SP.AFP) AS AFP_TOTAL, tbl_SP.T1_UNIT " _
& "FROM tbl_SP " _
& "GROUP BY tbl_SP.T1_UNIT " _
& "HAVING (((tbl_SP.T1_UNIT)='" & strUnit & "'));"
Set db = CurrentDb
Set rs = db.OpenRecordset(strSQL, dbOpenDynaset)
AFP_Total = rs!AFP_Total
There is an even simpler way to calculate the total percentage.
Instead of looping through the records, you can use the DSum() function.
Note that DSum will return Null if there are no records, so you need to wrap it in Nz().
Just for fun, here is your function but written as one single statement:
Function RemainingPercentAvailable() As String
RemainingPercentAvailable = "Remaining available: " & Format(1 - _
Nz(DSum("Percentage", _
"tbl_CustomPercent", _
"Tier1 = " & QString(cmbImport_T1) & _
" AND [Month] = " & QString(cmbMonth))) _
, "0.000%")
End Function
I don't recommend building a temporary parameterized query in VBA, because it makes the code too complicated. And slower. I prefer to build "pure" SQL that will run directly in the db engine without any callbacks to Access. I'm assuming that your function is defined in the frmEntry form, and that cmbImport_T1 and cmbMonth are string fields. If they are numeric, omit qString().
Here is my version of your function. It handles the empty-recordset case correctly.
Function RemainingPercentAvailable() As String
Dim CurrentTotal As Double, q As String
q = "SELECT Percentage" & _
" FROM tbl_CustomPercent" & _
" WHERE Tier1 = " & QString(cmbImport_T1) & _
" AND [Month] = " & QString(cmbMonth)
CurrentTotal = 0
With CurrentDb.OpenRecordset(q)
While Not .EOF
CurrentTotal = CurrentTotal + .Fields("Percentage")
.MoveNext
Wend
End With
RemainingPercentAvailable = "Remaining available: " & _
Format(1 - CurrentTotal, "0.000%")
End Function
' Return string S quoted, with quotes escaped, for building SQL.
Public Function QString(ByVal S As String) As String
QString = "'" & Replace(S, "'", "''") & "'"
End Function