Dynamically generate report source

C

Cheese_whiz

I have a form where, among other things, users choose a query against which
to run a report. There are three queries. I was hoping to be able to use
the same report in a case where one report needs to be capable of being run
against more than one query by somehow dynamically adding the name of the
report control source.

Is that possible? I know I could make different copies of a report with
slightly different names and then set them to use different control sources
such that I'd get the desired end results, but can I do it using one report
despite needing to run the report using different queries depending on user
selections?

Hope that's clear...happy to clarify more if I can.

Thanks,
CW
 
C

Cheese_whiz

Edit: My reports are being opened using the DoCmd.OpenReport and I'm using
variables to represent the report name (based on selection in one list box)
and the where statement (based on a selections in a variety of other
controls).

CW
 
A

Albert D. Kallal

If the report is the same, and you are ONLY changing the criteria...then
why have 3 different query's?

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.
 
C

Cheese_whiz

Very informative, Albert,

I don't know why I didn't think about getting rid of the criteria in the
query design before posting, but I didn't and I'm glad I didn't now (thanks
to your informative reply).

Just to clarify one point: If my query has '<>3' in the criteria under the
'status' column in design view, and I make a Docmd.openform (or report) that
includes a 'where' clause which, among other things, includes 'status=<3',
then I'm assumming that where clause will NOT overwrite/replace what's in the
criteria row of the status column of the query, correct?

Thanks a lot for the help.
CW

Albert D. Kallal said:
If the report is the same, and you are ONLY changing the criteria...then
why have 3 different query's?

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.
Click to expand...
 
A

Albert D. Kallal

includes a 'where' clause which, among other things, includes 'status=<3',
then I'm assumming that where clause will NOT overwrite/replace what's in
the
criteria row of the status column of the query, correct?
Click to expand...

yes, you can place criteria in the query...and the "where" clause will be an
additional criteria...it will not overwrite the query conditions....
 
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