Why don't you just move remove the parameters from the query altogether, and
have the form with supposed dahlias and that pass the values it needs via a
where clause.
As you are finding out, putting forms! expression in queries can get really
messy real fast.
Even worse, is now that the query is now "married" and attached to that ONE
form. Often, I have a nice query that I could use MANY times for different
reports, and often even that same query could be used for reports...but then
someone comes along and puts in a expression that means the query is ONLY
good when that form is opened.
Worse, is very hard to control things like having 5 combo boxes, but the
user only selects restrictions in 3 of the combo boxes...and wants the other
2 to be ignore.
I could probably write another 10 or pages as to why putting forms
expressions in queries is bad (besides...it makes the queries real ugly, and
hard to read. and, the sql then is not standard anymore (it will not work
with server based systems either).
So, the solution use now is simply to take the values from the form, and
build your own where clause in code. That way, you simply design the reports
(or forms), and attached them to the query, BUT NO FORMS! conditions are
placed in the query.
To "send" the conditions to the report (or form), you simply use the "where"
clause. This is exactly why ms-access has this feature...and it solves a
zillion problems...and will reduce your development costs by a substantial
amount.
Take a look at the following screen shots to see what I mean:
http://www.members.shaw.ca/AlbertKallal/ridesrpt/ridesrpt.html
The code to make those above screens work and launch the report with the
selected restrictions when you hit the "print" button is easy:
dim strWhere as string
' select sales rep combo
if isnull(cboSalesRep) = false then
strWhere = "SalesRep = '" & cboSalesRep & "'"
end if
' select what City for the report
if isnull(cboCity) = false then
if strWhere <> "" then
strWhere = strWhere " and "
endif
strWhere = strWhere & "City = '" & cobCity & "'"
end if
Note how the 2nd combo test is setup. You can add as "many" more conditions
you want. Lets say we have a check box to only include Special Customers. We
can add to our very nice prompt screen a check box to
[x] Show Only Special customers
The code we add would be:
if chkSpeicalOnly = True then
if strWhere <> "" then
strWhere = strWhere " and "
endif
strWhere = strWhere & "SpecialCust = true"
endif
For sure, each combo and control we add to the nice report screen takes a
bit of code, but no more messy then the query builder..and this way, each
query is nice and clean, and free of a bunch of HIGHLY un-maintainable
forms! expressions.
Further, it means you can re-use the same query for different reports, and
have no worries about some form that is supposed to be open. So, a tiny bit
more code eliminates the messy query problem.. For me, this is very worth
while trade.
So simply have form pass the restrictions by a where clause.....
If you don't want the user to open the form if the value is missing, then
you can simply just put it in code and use the is null function before you
try to open the form.
and if you don't want users to open the form and left are launching it from
the parameter form, then just put the following in the on open event:
if isloaded("nameOfParamForm") = false then
msgbox "do not open form unless prompt form is being used"
cancel = true
end if
