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How do I count Nulls and not nulls at the same time?

I have a view in SQL server 2005, that I use as my reports data.

My records typically looks like this:

ProvinceID      PID      Province CID      CName      CityID      CityName      Votes
20815      20815      Gauteng      208117      Pretoria      208117      Pretoria      321
20815      20815      Gauteng      208117      Pretoria      208117      Pretoria      386
20815      20815      Gauteng      208117      Pretoria      208117      Pretoria      311
20815      20815      Gauteng      208117      Pretoria      208117      Pretoria      323
20815      20815      Gauteng      208117      Pretoria      208117      Pretoria      321
20815      20815      Gauteng      208118      Boksburg      208118      Boksburg      218
20815      20815      Gauteng      208118      Boksburg      208118      Boksburg      320
20815      20815      Gauteng      208118      Boksburg      208118      Boksburg      430
20815      20815      Gauteng      208118      Boksburg      208118      Boksburg      340
20815      20815      Gauteng      208118      Boksburg      208118      Boksburg      350
10101      10101      KZN      101001      Durban      101001      Durban      40
NULL      10101      KZN      NULL      NULL      101002      Maritzburg      NULL
NULL      10101      KZN      NULL      NULL      101003      East London      NULL
NULL      10101      KZN      NULL      NULL      101004      Umhlanga      NULL
NULL      10101      KZN      NULL      NULL      101005      Salt Rock      NULL
NULL      10102      CPT      NULL      NULL      101006      Bellville      NULL

My desired outcome is:

Province      Total Cities with no votes        Total Cites
Gauteng      0        10
KZN      4        5
CPT      1        1

I group by PID, then I need to count all the Cities per Province where CID is NULL and where CID is not NULL (all the cities per province).

I can't seem to get it right!

Please advise.

peter57r

You wil have to count the nulls in a formula field. Yu need 3 formula fields altogether.

In the group header:

WhilePrintingRecords;
Numbervar NullKnt:=0;
""

In the Detail line:

WhilePrintingRecords;
if isnull({table.CID}) then NullKnt:=NullKnt+1;
""
In the group Footer you display the count using a 3rd formula field.:

WhilePrintingRecords;
Numbervar NullKnt;
NullKnt

Kevin Cross

To do this from the SQL side, you would just do something like this:

SELECT Province
, SUM(CASE WHEN CID IS NULL THEN 1 ELSE 0 END) AS [Total Cities with no votes]
, SUM(CASE WHEN CID IS NOT NULL THEN 1 ELSE 0 END) AS [Total Cities]
FROM ProvinceTable

Open in new window

Kevin Cross

Sorry hit submit too quickly:

SELECT Province
, SUM(CASE WHEN CID IS NULL THEN 1 ELSE 0 END) AS [Total Cities with no votes]
, SUM(CASE WHEN CID IS NOT NULL THEN 1 ELSE 0 END) AS [Total Cities]
FROM ProvinceTable
GROUP BY Province

Open in new window

Kurt Reinhardt

Even easier, why not just use the Running Total field (assuming you're using CR7 or greater and it looks like you're using 2008)? Each running total field has three parts:

Field to Summarize - in this case it's the CID field and you'll count the field
Evaluate - select "use a formula" and type in isnull({table.CID}) for the running total to count no votes and not isnull({table.CID}) for the running total to count cities with votes
Reset - in your case, the running total needs to be reset on either the POD or Province fields - if you have an actual group for either of these fields, then use that, else use the field itself...

You will need to create two running totals, one for each type of count, but this is simpler than creating a manual running total that has 3 formulas for each count

Lalla Belle

ASKER

mwvisa1:

When I run the query, the output is

CID      Total Cities with no votes      Total Cities
20809      6        0
20810      6        0
20811      0        50
20812      0        45
20813      0        45
20814      0        50
20815      0        55

It works fine when There are no nulls, but the 'Total cities' should equal the 'Total Cities with no votes' when they are null, now it says 0?

Thanks

Kevin Cross

I got you. I thought the you wanted the count of NULLs and count of NOT NULLs.

Am I understanding better now that you want count of NULLs and then count of ALL including nulls?

If so, think this should work:

SELECT Province
, SUM(CASE WHEN CID IS NULL THEN 1 ELSE 0 END) AS [Total Cities with no votes]
, SUM(*) AS [Total Cities]
FROM ProvinceTable
GROUP BY Province

Open in new window

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Kevin Cross

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Lalla Belle

ASKER

Thanks, enjoy the coffee!

Kevin Cross

You are most welcome!!