VBA (Access 2016) UPDATE Query - ms-access

Question

I've run into a problem with using a variable in a SQL Update Query in Access 2016. I have a logic field that will get updated based on a previously defined logic.
In this example, Package_Status is a Yes/No logic field in TableName.
This works:
strSQL ="UPDATE TableName SET [Package_Status] = TRUE"
dbName.Execute strSQL
This does NOT work:
xlogic = True
strSQL = "UPDATE TableName SET [Package_Status] = '" & xlogic & "'"
dbName.Execute strSQL
I'm sure the reason is obvious but I'm stumped! Why doesn't the second example work?

Answer 1

The way out of such misery is to print out what you build:
xlogic = True
strSQL = "UPDATE TableName SET [Package_Status] = '" & xlogic & "'"
Debug.Print strSQL
That will reveal why:
UPDATE TableName SET [Package_Status] = 'True'
Alternatively, when concatenating SQL, you can use my CSql function:
' Converts a value of any type to its string representation.
' The function can be concatenated into an SQL expression as is
' without any delimiters or leading/trailing white-space.
'
' Examples:
' SQL = "Select * From TableTest Where [Amount]>" & CSql(12.5) & "And [DueDate]<" & CSql(Date) & ""
' SQL -> Select * From TableTest Where [Amount]> 12.5 And [DueDate]< #2016/01/30 00:00:00#
'
' SQL = "Insert Into TableTest ( [Street] ) Values (" & CSql(" ") & ")"
' SQL -> Insert Into TableTest ( [Street] ) Values ( Null )
'
' Trims text variables for leading/trailing Space and secures single quotes.
' Replaces zero length strings with Null.
' Formats date/time variables as safe string expressions.
' Uses Str to format decimal values to string expressions.
' Returns Null for values that cannot be expressed with a string expression.
'
' 2016-01-30. Gustav Brock, Cactus Data ApS, CPH.
'
Public Function CSql( _
ByVal Value As Variant) _
As String
Const vbLongLong As Integer = 20
Const SqlNull As String = " Null"
Dim Sql As String
Dim LongLong As Integer
#If Win32 Then
LongLong = vbLongLong
#End If
#If Win64 Then
LongLong = VBA.vbLongLong
#End If
Select Case VarType(Value)
Case vbEmpty ' 0 Empty (uninitialized).
Sql = SqlNull
Case vbNull ' 1 Null (no valid data).
Sql = SqlNull
Case vbInteger ' 2 Integer.
Sql = Str(Value)
Case vbLong ' 3 Long integer.
Sql = Str(Value)
Case vbSingle ' 4 Single-precision floating-point number.
Sql = Str(Value)
Case vbDouble ' 5 Double-precision floating-point number.
Sql = Str(Value)
Case vbCurrency ' 6 Currency.
Sql = Str(Value)
Case vbDate ' 7 Date.
Sql = Format(Value, " \#yyyy\/mm\/dd hh\:nn\:ss\#")
Case vbString ' 8 String.
Sql = Replace(Trim(Value), "'", "''")
If Sql = "" Then
Sql = SqlNull
Else
Sql = " '" & Sql & "'"
End If
Case vbObject ' 9 Object.
Sql = SqlNull
Case vbError ' 10 Error.
Sql = SqlNull
Case vbBoolean ' 11 Boolean.
Sql = Str(Abs(Value))
Case vbVariant ' 12 Variant (used only with arrays of variants).
Sql = SqlNull
Case vbDataObject ' 13 A data access object.
Sql = SqlNull
Case vbDecimal ' 14 Decimal.
Sql = Str(Value)
Case vbByte ' 17 Byte.
Sql = Str(Value)
Case LongLong ' 20 LongLong integer (Valid on 64-bit platforms only).
Sql = Str(Value)
Case vbUserDefinedType ' 36 Variants that contain user-defined types.
Sql = SqlNull
Case vbArray ' 8192 Array.
Sql = SqlNull
Case Else ' Should not happen.
Sql = SqlNull
End Select
CSql = Sql & " "
End Function