Question

I need to combine fields and then trim out extra spaces the middle of a text field. With Access it’s easy for me but creating a SQL Function eludes me. This is how I do it in Access, anyone able to help me create a SQL Function?

In VBA Access Query I can do this with the following code in query:

FullTrim([tblLeadsResi].[House Number] & [tblLeadsResi].[Street] & " " & 
    [tblLeadsResi].[Street Suffix] & " " & [tblLeadsResi].[Post-directional] & 
    IIf(Not IsNull([tblLeadsResi].[Apartment Number])," #" & 
    [tblLeadsResi].[Apartment Number],""))

Module Code in Access: (Basically if it’s a double space it doesn’t add the first space back in)

Public Function FullTrim(stText As String) As Variant
Dim intLen As Integer, stPart As String, stBlank As String, stNewText As String

    '   ++++++++++++++++++++++++++++++++++++++++++++++++++++++++
    '   ++++    Takes any spaces away from a Text Value     ++++
    '   ++++++++++++++++++++++++++++++++++++++++++++++++++++++++

    If IsNull(stText) Or stText = "" Then
        FullTrim = ""
    Else
        For intLen = 1 To (Len(stText) - 1)
            stPart = Mid(stText, intLen, 1)
            stBlank = Mid(stText, intLen, 2)
            If stBlank <> "  " Then
                stNewText = stNewText & stPart
            End If
        Next intLen

        intLen = Len(stText)
        stPart = Mid(stText, intLen, 1)
        stNewText = stNewText & stPart

        stNewText = Trim(stNewText)
        FullTrim = stNewText
    End If
End Function

Answer 1

Creation

CREATE FUNCTION dbo.FullTrim(@Value NVARCHAR(MAX))
RETURNS NVARCHAR(MAX)
AS
BEGIN
    DECLARE @Subs NVARCHAR(6)
    SET @Subs = '~@$$#%' -- Make this some string you will never have in your data
    RETURN LTRIM(RTRIM(REPLACE(REPLACE(REPLACE(@Value, '  ', ' ' + @Subs), @Subs + ' ', ''), @Subs, '')))
END

Usage

SELECT dbo.FullTrim('  This is a     string      with    many spaces ')

Result

This is a string with many spaces