Determining EVERY month between 2 given dates

Hi everyone, I have a table with the following data upon which I would
like to report:

SomeDt SomeValue
1-sep-09 100
12-dec-09 200
02-feb10 50
14-apr-10 75

I need to report on this data showing values for all months within the
given min and max dates on the file so:
These dates need to be part of a *rolling* report.

I have data for Sep, Dec,Feb and Apr, but I want to display on the
report ALL months regardless of whether they have data in the table
and return 0 where they do not. Thus:

Month Value
Sep 09 100
Oct 09 0
Nov 09 0
Dec 09 200
Jan 10 0
Feb 10 50
Mar 10 0
Apr 10 75


I can get the min and max and the count of months easily enough:

select min(SomeDt) as StDt, max(SomeDt) as EndDt, datediff("m" , StDt,
EndDt) as CountofMonthsBetween from SomeTable

What I cannot get is how to then determine what the months are in
between. What I want if possible is a resultset that looks something
like this

StDt EndDt Mth
01/9/09 14/4/10 Sep 09
01/9/09 14/4/10 Oct 09
01/9/09 14/4/10 Nov 09
01/9/09 14/4/10 Dec 09
01/9/09 14/4/10 Jan 10
01/9/09 14/4/10 Feb 10
01/9/09 14/4/10 Mar 10
01/9/09 14/4/10 Apr 10

How can I do it?

As much as possible I want to use QUERY resultsets, rather than
creating intermediary tables etc which are just messy in MS Access,
but will use them if no other choice.

Happy to write a function if needs be to calc the Mth column. Am
absolutely desperate so all help greatly appreciated. If it can't be
done at all via queries alone, please let me know this too.

Edwina63

The missing months have to come from somewhere, so you need a table to
generate them.

1. Create a new table with just one field named (say) CountID, type Number,
and mark it as primary key. Save the table as (say) tblCount.

2. Enter records into this table, from zero to the largest number of months
you will need for your report. If there could be a large number of months,
here's some code to enter the records for you:
http://allenbrowne.com/ser-39.html

3. Create a query using tblCount as the source table.
Drag CountID into the grid. In the Criteria row under this field, enter:
[How many months?]

4. Type this expression into the next column, the Field row:
TheMonth: DateAdd("m", [CountID], [StartMonth])

5. Declare the Parameters (Parameters on ribbon or Query menu.)
Access opens the Parameters dialog.
Enter 2 rows, using exactly the same names as you used above:
[How many months?] Long
StartMonth Date/Time

6. Test. This should generate a record for every month.
Save the query as qryCount.

7. Create a query using your existing table.
Enter this expression into the Field row:
MonthStart: [SomeDt] - Day([SomeDt]) + 1

8. Depress the Total button on the toolbar/ribbon.
Access adds a Total row to the design grid.
Accept Group By under this field.

9. Drag SomeValue into the grid.
In the Total row under this field, choose Sum.
Test: the query will give you one total for each month that has data.
Save the query as qryMonthData.

10. Create another query using qryCount and qryMonthData as input 'tables'.

11. Drag qryCount.TheMonth onto qryMonthData.MonthStart.
Access draws a line between the two tables.

12. Double-click the line between the 2 dialogs.
Access opens a dialog with 3 options.
Choose the one that says:
All records from qryCount, and any matches from qryMonthData.

(Technically, that's known as an outer join, and it's what gives you every
month.)

--
Allen Browne - Microsoft MVP. Perth, Western Australia
Tips for Access users - http://allenbrowne.com/tips.html
Reply to group, rather than allenbrowne at mvps dot org.


"Edwinah63" wrote in message
...
Hi everyone, I have a table with the following data upon which I would
like to report:

SomeDt SomeValue
1-sep-09 100
12-dec-09 200
02-feb10 50
14-apr-10 75

I need to report on this data showing values for all months within the
given min and max dates on the file so:
These dates need to be part of a *rolling* report.

I have data for Sep, Dec,Feb and Apr, but I want to display on the
report ALL months regardless of whether they have data in the table
and return 0 where they do not. Thus:

Month Value
Sep 09 100
Oct 09 0
Nov 09 0
Dec 09 200
Jan 10 0
Feb 10 50
Mar 10 0
Apr 10 75


I can get the min and max and the count of months easily enough:

select min(SomeDt) as StDt, max(SomeDt) as EndDt, datediff("m" , StDt,
EndDt) as CountofMonthsBetween from SomeTable

What I cannot get is how to then determine what the months are in
between. What I want if possible is a resultset that looks something
like this

StDt EndDt Mth
01/9/09 14/4/10 Sep 09
01/9/09 14/4/10 Oct 09
01/9/09 14/4/10 Nov 09
01/9/09 14/4/10 Dec 09
01/9/09 14/4/10 Jan 10
01/9/09 14/4/10 Feb 10
01/9/09 14/4/10 Mar 10
01/9/09 14/4/10 Apr 10

How can I do it?

As much as possible I want to use QUERY resultsets, rather than
creating intermediary tables etc which are just messy in MS Access,
but will use them if no other choice.

Happy to write a function if needs be to calc the Mth column. Am
absolutely desperate so all help greatly appreciated. If it can't be
done at all via queries alone, please let me know this too.

Edwina63

Hi Allen,

Thanks for your solution, it is very neat. Now let me ask the truly
stoopid question: is it possible to generate those eight records that
are put into tblCount via a query alone ie: based on the the record
count (in this example 8 months between Sep and Apr), is it possible
to force a *query* to return 8 records (containing 1 to 8, 0 to 7 or
whatever)?

I am certain the answer is no, but I am interested to have that
confirmed by someone who knows Access well (or queries in general and
likes a challenge!). As a quick background, I am used to doing these
sorts of things in MS SQL stored procs. I would create the kind of
table you suggested as a temp table within the procedure and outer
join that table back to my query containing the data all as you have
outlined. The advantage of stored procs is that when they go out of
scope, all the temp tables I have created are destroyed with them.

I am worried about creating the table because once I have the final
resultset I want all the intermediary steps destroyed. This is coupled
with the fact that the owner of this database wants it to be as
codeless as possible. Hence the idea of forcing a query to return 8
records in a resultset (which seems to be the nearest thing to a temp
table I can find in Access).

Any suggestions as the best way to approach this?

Edwinah63

ps not sure how i would go about forcing a query to return 8 empty
records in ms sql either!! :-) so over to the floor!

ps not sure how i would go about forcing a query to return 8 empty
records in ms sql either!! :-) so over to the floor!

Bite the bullet. Create the tblDates table and then use it in your query.
Then you'll create a deliberate partial cartesian product, constraining the
dates to be between a start and end date.

--
Message posted via AccessMonster.com
http://www.accessmonster.com/Uwe/For...eries/201005/1

Do you already have a table in your database that contains an autonumber
field? If so, use that instead of creating a new table.
Otherwise, a dynamic solution is not possible. You can of course hard-code
some unioned queries to force the missing records to be included.

As an alternative, create a new database in code, create the Numbers table
in it, link to it, and use it in your query, deleting the database when
finished. I'm sure Allen has an example of VBA code to create a database on
his website. If not, try www.rogersaccesslibrary.com

As for SQL Server, given the existence of a Numbers table, the exact same
solution is possible without the overhead of temp tables.

Edwinah63 wrote:
Hi Allen,

Thanks for your solution, it is very neat. Now let me ask the truly
stoopid question: is it possible to generate those eight records that
are put into tblCount via a query alone ie: based on the the record
count (in this example 8 months between Sep and Apr), is it possible
to force a *query* to return 8 records (containing 1 to 8, 0 to 7 or
whatever)?

I am certain the answer is no, but I am interested to have that
confirmed by someone who knows Access well (or queries in general and
likes a challenge!). As a quick background, I am used to doing these
sorts of things in MS SQL stored procs. I would create the kind of
table you suggested as a temp table within the procedure and outer
join that table back to my query containing the data all as you have
outlined. The advantage of stored procs is that when they go out of
scope, all the temp tables I have created are destroyed with them.

I am worried about creating the table because once I have the final
resultset I want all the intermediary steps destroyed. This is coupled
with the fact that the owner of this database wants it to be as
codeless as possible. Hence the idea of forcing a query to return 8
records in a resultset (which seems to be the nearest thing to a temp
table I can find in Access).

Any suggestions as the best way to approach this?

Edwinah63

ps not sure how i would go about forcing a query to return 8 empty
records in ms sql either!! :-) so over to the floor!

--
Microsoft MVP - ASP/ASP.NET - 2004-2007
Please reply to the newsgroup. This email account is my spam trap so I
don't check it very often. If you must reply off-line, then remove the
"NO SPAM"

FWIW,
here's Tony's explanation of how to use Temp Tables in Access....
http://www.granite.ab.ca/access/temptables.htm

not quite the same as SQL Server, but the best you're going to do in Access...


--
Message posted via http://www.accessmonster.com

You can of course hard-code
some unioned queries to force the missing records to be included.

D'oh! I completely forgot about creating a dynamic union query! Thank
you for reminding me!

Maybe something like this?

public sub CreateAQuery(mthsBetween as integer)

dim i as integer
dim sql as string

for i = 0 to mthsBetween

sql = sql & "select " & i & " as Mth union "

next i

------Can I do this next bit??---

Currentdb.Execute " If exists(SELECT name FROM sysobjects WHERE name =
'MyUnionQuery' DROP QUERY MyUnionQuery;"
CurrentDb.Execute "CREATE QUERY MyUnionQuery AS " & sql


end sub

The code above isn't quite right but you get the idea.

Had a hunt around the internet for a "Create Query" statement. Is
there one? Would prefer to stick to SQL statements wherever possible
but will use querydefs etc otherwise.

A big thank you to everyone who responded :-)

Edwinah63 wrote:
You can of course hard-code
some unioned queries to force the missing records to be included.

D'oh! I completely forgot about creating a dynamic union query! Thank
you for reminding me!

Maybe something like this?

public sub CreateAQuery(mthsBetween as integer)

dim i as integer
dim sql as string

for i = 0 to mthsBetween

sql = sql & "select " & i & " as Mth union "

next i

------Can I do this next bit??---

Currentdb.Execute " If exists(SELECT name FROM sysobjects WHERE name =
'MyUnionQuery' DROP QUERY MyUnionQuery;"
CurrentDb.Execute "CREATE QUERY MyUnionQuery AS " & sql


end sub

The code above isn't quite right but you get the idea.

Had a hunt around the internet for a "Create Query" statement. Is
there one? Would prefer to stick to SQL statements wherever possible
but will use querydefs etc otherwise.

A big thank you to everyone who responded :-)

Aside from the test for existence: absolutely. In this case, it would be

CREATE VIEW view [(field1[, field2[, ...]])] AS selectstatement

If you parameterize it or create an action query, it would be

CREATE PROCEDURE procedure
[param1 datatype[, param2 datatype[, ...]] AS sqlstatement

Online help has a well-hidden section on JetSQL, but I did manage to find it
:-)
Just hit F1, find the again well-hidden link on the help screen to get to
the table of contents, and find the node called "Microsoft Jet SQL
Reference" - the last bit isn't so hard :-)

You would have to look at the querydefs collection (if using DAO) or the
ADOX Views or Procedures collection (if using ADO) to find out if the query
exists. But you know ... since you're already into the Querydefs collection,
you might as well simply use a querydef object ... it will truly be
temporary if you omit the qryname argument from the CreateQuerydef
statement. Since you are using VBA, you're code won't be portable anyways,
so you might as well do it the easy way.

Oh! And don't forget: unlike Transact-SQL, Jet SQL requires a FROM clause
with table expression. You don't have to actually retrieve any data from the
table, but you do have to name one.

Transact-SQl:
Select 'a' as col1, 2 as col2
union
Select 'b', 4

Jet SQL:
Select TOP 1 'a' as col1, 2 as col2 FROM existingtable

union
Select TOP 1 'b', 4 FROM existingtable

--
Microsoft MVP - ASP/ASP.NET - 2004-2007
Please reply to the newsgroup. This email account is my spam trap so I
don't check it very often. If you must reply off-line, then remove the
"NO SPAM"

Thanks for your reply. I am having trouble now with the Create View
Statement.

To check I had the right syntax I created a dummy table with 1 field,
1 record. I then created the sample statement in the SQL view of both
an ordinary and so called "Data Definition" query

create view MyView as select dummyid from tblDummy

Both come back with the error "Syntax error in Create Table statement"

What am I doing wrong?

Had a google around and it seems that Access 2007 will not recognize
create view statement for this database unless the ANSI92
compatibility is turned on and the ANSI92 option under Access Options/
Object Designers/Query Design/Sql Server Compatible Syntax is greyed
out.

Database is an Access 2007 database looking at Access 2007 tables
within the same database. I really want to avoid the whole querydefs
thing if I can.

Are you sure that JetSQL supports the DDL statements Create View/
Procedure? If so may I have the full steps please?

Edwinah63 wrote:
Thanks for your reply. I am having trouble now with the Create View
Statement.

To check I had the right syntax I created a dummy table with 1 field,
1 record. I then created the sample statement in the SQL view of both
an ordinary and so called "Data Definition" query

create view MyView as select dummyid from tblDummy

Both come back with the error "Syntax error in Create Table statement"

What am I doing wrong?

Had a google around and it seems that Access 2007 will not recognize
create view statement for this database unless the ANSI92
compatibility is turned on and the ANSI92 option under Access Options/
Object Designers/Query Design/Sql Server Compatible Syntax is greyed
out.

Database is an Access 2007 database looking at Access 2007 tables
within the same database. I really want to avoid the whole querydefs
thing if I can.

Are you sure that JetSQL supports the DDL statements Create View/
Procedure? If so may I have the full steps please?

I can't give you any more than what is in the online help .. sorry.
In A2003, I did have to check the ANSI92 option for the database I was
testing with in order to make the CREATE VIEW statement work in the SQL View
of a query builder window. Without that option turned on, I got the same
error you did.

This snippet of code also failed until I turned on ANSI92:

Sub testcreateview()
Dim db As DAO.Database
Set db = CurrentDb
db.Execute "CREATE VIEW testqry AS select * from table1", dbFailOnError
End Sub

If you cannot turn on that option, it appears you will have to resort to the
querydef (or ADOX Views) method. I'm baffled as to why you are so desperate
to avoid it. Is it because of the need to create a Reference to DAO? If so,
you can do that in code by using the Application object's References
collection, which has two methods for creating references: AddFromFile and
AddFromGuid. Here is an example of the latter:

Dim ref As Reference, DAOfound As Boolean
DAOfound = False
For Each ref In Application.References
If ref.Name = "DAO" Then
DAOfound = True
exit for
End If
Next ref
If Not DAOfound Then
Application.References.AddFromGuid
"{00025E01-0000-0000-C000-000000000046}", 3, 6
End If


They are very simple to use. You don't even have to drop the querydef if
you've already created it - just set the .SQL property to the new sql
statement, like this:

sub createqry()
dim db as database,qdf as querydef,strsql as string
'build your string
set db=currentdb
on error resume next
set qdf=db.querydefs("qryname")
if err 0 then set qdf=db.createquerydef("qryname")
qdf.sql=strsql
end sub

--
Microsoft MVP - ASP/ASP.NET - 2004-2007
Please reply to the newsgroup. This email account is my spam trap so I
don't check it very often. If you must reply off-line, then remove the
"NO SPAM"