Concatenate in Access 2000 - sql

Question

I have searched 'concatenate' topics and have been unable to find the answer I need. This posting came close access sql query to concatenate rows but my attempts to make it work for my purpose failed.
What I have is a table like this
Lic# | Permit | Year
------------------------
1 | NS1 | 2003
1 | NS1 | 2004
1 | NS2 | 2004
2 | TR | 2012
2 | NS2 | 2012
3 | OR | 2008
2 | OR | 2011
2 | NS1 | 2011
2 | TR | 2011
....And so forth. This table has many unique license numbers with permit type and year (from 2003-2012) listed for each.
What I would like is to create a table that would display the information like this
Lic# | Permit | Year
-----------------------------
1 |NS1 | 2003
1 | NS1, NS2 | 2004
2 | TR, NS2 | 2012
3 | OR | 2008
2 | OR, NS1, TR | 2011

Answer 1

As I posted in my comment, this is easy using the group_concat() function in MySQL, but if you want to do it in MS Access, I think you have to deal with this using VBA.
I propose you this function:
public function concatenatePermits(licNo as integer, year as integer)
dim db as DAO.database, rec as DAO.recordset, strSQL as string
dim ans as string
set db = currentdb()
strSQL = "select permit from [your table] " & _
"where [lic#]=" & licNo & " and year=" & year & ";"
set rec = db.openrecordset(strSQL, dbOpenDynaset, dbReadOnly)
ans = ""
with rec
.moveFirst
do
if ans = "" then
ans = !permit
else
ans = ans & "," & !permit
end if
loop until .EOF
end with
rec.close
db.close
concatenatePermits = ans
end function
This function can be used in any query. Downside: If your table is really big, the execution of a query that uses this function can be really slow. I think the better approach would be to create an empty table and then fill it row by row using VBA.
Hope this helps you.
Adding rows using VBA
In your comment you ask how to add rows to a table with VBA. Assuming the table exists and you have the data you want to feed into this table, I suggest you something like this:
public sub addData()
dim db as dao.database, recOut as dao.recordset
' Declare all the variables you need for your code'
set db = currentdb()
' recOut will be the table where you want to store your data '
set recIn = db.openRecordset("tblYourOutTable",dbOpenDynaset,dbEditAdd)
' At some point in your code you will need to store data in your table: '
with recOut
.addNew
![A_Field] = value1
![Another_field] = value2
![Yet_another_field] = value3
.update
end with
' Close the recordset and the database objects '
rec.close
db.close
end sub