Track changes on 2+ columns using OUTPUT clause

Track changes on 2+ columns using OUTPUT clause - sql

I have a dbo.ChangeLog table that we insert changes to certain columns.
The normal way I do this is something along the lines of:
UPDATE dbo.Table
SET FirstName = NewFirstName
OUTPUT
Deleted.Id
'FirstName' as Type
Deleted.FirstName as OldValue
Inserted.FirstName as NewValue
INTO dbo.ChangeLog
FROM dbo.Table as t
INNER JOIN dbo.Table2 as t2 on t.Id = t2.Id
When I need to update FirstName AND LastName, for example, I usually do 2 update statements, but I am wondering if it's possible to update multiple columns in the same update statement, while also inserting the changes into the dbo.ChangeLog table.

If you can change the definition of dbo.ChangeLog it becomes trivial, but I'm assuming that's not really what you want.
I'd handle this with a table variable and "unpivot" the data using CROSS APPLY (but would probably work fine using UNPIVOT too...):
SELECT 1 as id, 'Dan ' as FirstName, 'Field ' as LastName INTO #tbl
DECLARE #changes TABLE (id int, old1 varchar(250), new1 varchar(250), old2 varchar(250), new2 varchar(250))
UPDATE #tbl
SET FirstName = 'asdf', LastName = NEWID()
OUTPUT deleted.id
,deleted.FirstName, inserted.FirstName
,deleted.LastName, inserted.LastName
INTO #changes(id, old1, new1, old2, new2)
-- change this to an INSERT dbo.ChangeLog
SELECT unp.*
FROM #changes
CROSS APPLY (VALUES (id, old1, new1)
,(id, old2, new2)) unp(id, oldval, newval)
DROP TABLE #tbl
Just change that last SELECT into an INSERT. And note that this requires an intermediate table variable or temp table, because you can't use CROSS APPLY or UNPIVOT in an OUTPUT clause.

Related

INSERT inside an INSERT statement and use its ID in the outer INSERT [duplicate]

Very simplified, I have two tables Source and Target.
declare #Source table (SourceID int identity(1,2), SourceName varchar(50))
declare #Target table (TargetID int identity(2,2), TargetName varchar(50))
insert into #Source values ('Row 1'), ('Row 2')
I would like to move all rows from #Source to #Target and know the TargetID for each SourceID because there are also the tables SourceChild and TargetChild that needs to be copied as well and I need to add the new TargetID into TargetChild.TargetID FK column.
There are a couple of solutions to this.
Use a while loop or cursors to insert one row (RBAR) to Target at a time and use scope_identity() to fill the FK of TargetChild.
Add a temp column to #Target and insert SourceID. You can then join that column to fetch the TargetID for the FK in TargetChild.
SET IDENTITY_INSERT OFF for #Target and handle assigning new values yourself. You get a range that you then use in TargetChild.TargetID.
I'm not all that fond of any of them. The one I used so far is cursors.
What I would really like to do is to use the output clause of the insert statement.
insert into #Target(TargetName)
output inserted.TargetID, S.SourceID
select SourceName
from #Source as S
But it is not possible
The multi-part identifier "S.SourceID" could not be bound.
But it is possible with a merge.
merge #Target as T
using #Source as S
on 0=1
when not matched then
insert (TargetName) values (SourceName)
output inserted.TargetID, S.SourceID;
Result
TargetID SourceID
----------- -----------
2 1
4 3
I want to know if you have used this? If you have any thoughts about the solution or see any problems with it? It works fine in simple scenarios but perhaps something ugly could happen when the query plan get really complicated due to a complicated source query. Worst scenario would be that the TargetID/SourceID pairs actually isn't a match.
MSDN has this to say about the from_table_name of the output clause.
Is a column prefix that specifies a table included in the FROM clause of a DELETE, UPDATE, or MERGE statement that is used to specify the rows to update or delete.
For some reason they don't say "rows to insert, update or delete" only "rows to update or delete".
Any thoughts are welcome and totally different solutions to the original problem is much appreciated.

In my opinion this is a great use of MERGE and output. I've used in several scenarios and haven't experienced any oddities to date.
For example, here is test setup that clones a Folder and all Files (identity) within it into a newly created Folder (guid).
DECLARE #FolderIndex TABLE (FolderId UNIQUEIDENTIFIER PRIMARY KEY, FolderName varchar(25));
INSERT INTO #FolderIndex
(FolderId, FolderName)
VALUES(newid(), 'OriginalFolder');
DECLARE #FileIndex TABLE (FileId int identity(1,1) PRIMARY KEY, FileName varchar(10));
INSERT INTO #FileIndex
(FileName)
VALUES('test.txt');
DECLARE #FileFolder TABLE (FolderId UNIQUEIDENTIFIER, FileId int, PRIMARY KEY(FolderId, FileId));
INSERT INTO #FileFolder
(FolderId, FileId)
SELECT FolderId,
FileId
FROM #FolderIndex
CROSS JOIN #FileIndex; -- just to illustrate
DECLARE #sFolder TABLE (FromFolderId UNIQUEIDENTIFIER, ToFolderId UNIQUEIDENTIFIER);
DECLARE #sFile TABLE (FromFileId int, ToFileId int);
-- copy Folder Structure
MERGE #FolderIndex fi
USING ( SELECT 1 [Dummy],
FolderId,
FolderName
FROM #FolderIndex [fi]
WHERE FolderName = 'OriginalFolder'
) d ON d.Dummy = 0
WHEN NOT MATCHED
THEN INSERT
(FolderId, FolderName)
VALUES (newid(), 'copy_'+FolderName)
OUTPUT d.FolderId,
INSERTED.FolderId
INTO #sFolder (FromFolderId, toFolderId);
-- copy File structure
MERGE #FileIndex fi
USING ( SELECT 1 [Dummy],
fi.FileId,
fi.[FileName]
FROM #FileIndex fi
INNER
JOIN #FileFolder fm ON
fi.FileId = fm.FileId
INNER
JOIN #FolderIndex fo ON
fm.FolderId = fo.FolderId
WHERE fo.FolderName = 'OriginalFolder'
) d ON d.Dummy = 0
WHEN NOT MATCHED
THEN INSERT ([FileName])
VALUES ([FileName])
OUTPUT d.FileId,
INSERTED.FileId
INTO #sFile (FromFileId, toFileId);
-- link new files to Folders
INSERT INTO #FileFolder (FileId, FolderId)
SELECT sfi.toFileId, sfo.toFolderId
FROM #FileFolder fm
INNER
JOIN #sFile sfi ON
fm.FileId = sfi.FromFileId
INNER
JOIN #sFolder sfo ON
fm.FolderId = sfo.FromFolderId
-- return
SELECT *
FROM #FileIndex fi
JOIN #FileFolder ff ON
fi.FileId = ff.FileId
JOIN #FolderIndex fo ON
ff.FolderId = fo.FolderId

I would like to add another example to add to #Nathan's example, as I found it somewhat confusing.
Mine uses real tables for the most part, and not temp tables.
I also got my inspiration from here: another example
-- Copy the FormSectionInstance
DECLARE #FormSectionInstanceTable TABLE(OldFormSectionInstanceId INT, NewFormSectionInstanceId INT)
;MERGE INTO [dbo].[FormSectionInstance]
USING
(
SELECT
fsi.FormSectionInstanceId [OldFormSectionInstanceId]
, #NewFormHeaderId [NewFormHeaderId]
, fsi.FormSectionId
, fsi.IsClone
, #UserId [NewCreatedByUserId]
, GETDATE() NewCreatedDate
, #UserId [NewUpdatedByUserId]
, GETDATE() NewUpdatedDate
FROM [dbo].[FormSectionInstance] fsi
WHERE fsi.[FormHeaderId] = #FormHeaderId
) tblSource ON 1=0 -- use always false condition
WHEN NOT MATCHED
THEN INSERT
( [FormHeaderId], FormSectionId, IsClone, CreatedByUserId, CreatedDate, UpdatedByUserId, UpdatedDate)
VALUES( [NewFormHeaderId], FormSectionId, IsClone, NewCreatedByUserId, NewCreatedDate, NewUpdatedByUserId, NewUpdatedDate)
OUTPUT tblSource.[OldFormSectionInstanceId], INSERTED.FormSectionInstanceId
INTO #FormSectionInstanceTable(OldFormSectionInstanceId, NewFormSectionInstanceId);
-- Copy the FormDetail
INSERT INTO [dbo].[FormDetail]
(FormHeaderId, FormFieldId, FormSectionInstanceId, IsOther, Value, CreatedByUserId, CreatedDate, UpdatedByUserId, UpdatedDate)
SELECT
#NewFormHeaderId, FormFieldId, fsit.NewFormSectionInstanceId, IsOther, Value, #UserId, CreatedDate, #UserId, UpdatedDate
FROM [dbo].[FormDetail] fd
INNER JOIN #FormSectionInstanceTable fsit ON fsit.OldFormSectionInstanceId = fd.FormSectionInstanceId
WHERE [FormHeaderId] = #FormHeaderId

Here's a solution that doesn't use MERGE (which I've had problems with many times I try to avoid if possible). It relies on two memory tables (you could use temp tables if you want) with IDENTITY columns that get matched, and importantly, using ORDER BY when doing the INSERT, and WHERE conditions that match between the two INSERTs... the first one holds the source IDs and the second one holds the target IDs.
-- Setup... We have a table that we need to know the old IDs and new IDs after copying.
-- We want to copy all of DocID=1
DECLARE #newDocID int = 99;
DECLARE #tbl table (RuleID int PRIMARY KEY NOT NULL IDENTITY(1, 1), DocID int, Val varchar(100));
INSERT INTO #tbl (DocID, Val) VALUES (1, 'RuleA-2'), (1, 'RuleA-1'), (2, 'RuleB-1'), (2, 'RuleB-2'), (3, 'RuleC-1'), (1, 'RuleA-3')
-- Create a break in IDENTITY values.. just to simulate more realistic data
INSERT INTO #tbl (Val) VALUES ('DeleteMe'), ('DeleteMe');
DELETE FROM #tbl WHERE Val = 'DeleteMe';
INSERT INTO #tbl (DocID, Val) VALUES (6, 'RuleE'), (7, 'RuleF');
SELECT * FROM #tbl t;
-- Declare TWO temp tables each with an IDENTITY - one will hold the RuleID of the items we are copying, other will hold the RuleID that we create
DECLARE #input table (RID int IDENTITY(1, 1), SourceRuleID int NOT NULL, Val varchar(100));
DECLARE #output table (RID int IDENTITY(1,1), TargetRuleID int NOT NULL, Val varchar(100));
-- Capture the IDs of the rows we will be copying by inserting them into the #input table
-- Important - we must specify the sort order - best thing is to use the IDENTITY of the source table (t.RuleID) that we are copying
INSERT INTO #input (SourceRuleID, Val) SELECT t.RuleID, t.Val FROM #tbl t WHERE t.DocID = 1 ORDER BY t.RuleID;
-- Copy the rows, and use the OUTPUT clause to capture the IDs of the inserted rows.
-- Important - we must use the same WHERE and ORDER BY clauses as above
INSERT INTO #tbl (DocID, Val)
OUTPUT Inserted.RuleID, Inserted.Val INTO #output(TargetRuleID, Val)
SELECT #newDocID, t.Val FROM #tbl t
WHERE t.DocID = 1
ORDER BY t.RuleID;
-- Now #input and #output should have the same # of rows, and the order of both inserts was the same, so the IDENTITY columns (RID) can be matched
-- Use this as the map from old-to-new when you are copying sub-table rows
-- Technically, #input and #output don't even need the 'Val' columns, just RID and RuleID - they were included here to prove that the rules matched
SELECT i.*, o.* FROM #output o
INNER JOIN #input i ON i.RID = o.RID
-- Confirm the matching worked
SELECT * FROM #tbl t

SQL Server, Select/Output/Insert - need to select value for output but not insert [duplicate]

In my opinion this is a great use of MERGE and output. I've used in several scenarios and haven't experienced any oddities to date.
For example, here is test setup that clones a Folder and all Files (identity) within it into a newly created Folder (guid).
DECLARE #FolderIndex TABLE (FolderId UNIQUEIDENTIFIER PRIMARY KEY, FolderName varchar(25));
INSERT INTO #FolderIndex
(FolderId, FolderName)
VALUES(newid(), 'OriginalFolder');
DECLARE #FileIndex TABLE (FileId int identity(1,1) PRIMARY KEY, FileName varchar(10));
INSERT INTO #FileIndex
(FileName)
VALUES('test.txt');
DECLARE #FileFolder TABLE (FolderId UNIQUEIDENTIFIER, FileId int, PRIMARY KEY(FolderId, FileId));
INSERT INTO #FileFolder
(FolderId, FileId)
SELECT FolderId,
FileId
FROM #FolderIndex
CROSS JOIN #FileIndex; -- just to illustrate
DECLARE #sFolder TABLE (FromFolderId UNIQUEIDENTIFIER, ToFolderId UNIQUEIDENTIFIER);
DECLARE #sFile TABLE (FromFileId int, ToFileId int);
-- copy Folder Structure
MERGE #FolderIndex fi
USING ( SELECT 1 [Dummy],
FolderId,
FolderName
FROM #FolderIndex [fi]
WHERE FolderName = 'OriginalFolder'
) d ON d.Dummy = 0
WHEN NOT MATCHED
THEN INSERT
(FolderId, FolderName)
VALUES (newid(), 'copy_'+FolderName)
OUTPUT d.FolderId,
INSERTED.FolderId
INTO #sFolder (FromFolderId, toFolderId);
-- copy File structure
MERGE #FileIndex fi
USING ( SELECT 1 [Dummy],
fi.FileId,
fi.[FileName]
FROM #FileIndex fi
INNER
JOIN #FileFolder fm ON
fi.FileId = fm.FileId
INNER
JOIN #FolderIndex fo ON
fm.FolderId = fo.FolderId
WHERE fo.FolderName = 'OriginalFolder'
) d ON d.Dummy = 0
WHEN NOT MATCHED
THEN INSERT ([FileName])
VALUES ([FileName])
OUTPUT d.FileId,
INSERTED.FileId
INTO #sFile (FromFileId, toFileId);
-- link new files to Folders
INSERT INTO #FileFolder (FileId, FolderId)
SELECT sfi.toFileId, sfo.toFolderId
FROM #FileFolder fm
INNER
JOIN #sFile sfi ON
fm.FileId = sfi.FromFileId
INNER
JOIN #sFolder sfo ON
fm.FolderId = sfo.FromFolderId
-- return
SELECT *
FROM #FileIndex fi
JOIN #FileFolder ff ON
fi.FileId = ff.FileId
JOIN #FolderIndex fo ON
ff.FolderId = fo.FolderId

I would like to add another example to add to #Nathan's example, as I found it somewhat confusing.
Mine uses real tables for the most part, and not temp tables.
I also got my inspiration from here: another example
-- Copy the FormSectionInstance
DECLARE #FormSectionInstanceTable TABLE(OldFormSectionInstanceId INT, NewFormSectionInstanceId INT)
;MERGE INTO [dbo].[FormSectionInstance]
USING
(
SELECT
fsi.FormSectionInstanceId [OldFormSectionInstanceId]
, #NewFormHeaderId [NewFormHeaderId]
, fsi.FormSectionId
, fsi.IsClone
, #UserId [NewCreatedByUserId]
, GETDATE() NewCreatedDate
, #UserId [NewUpdatedByUserId]
, GETDATE() NewUpdatedDate
FROM [dbo].[FormSectionInstance] fsi
WHERE fsi.[FormHeaderId] = #FormHeaderId
) tblSource ON 1=0 -- use always false condition
WHEN NOT MATCHED
THEN INSERT
( [FormHeaderId], FormSectionId, IsClone, CreatedByUserId, CreatedDate, UpdatedByUserId, UpdatedDate)
VALUES( [NewFormHeaderId], FormSectionId, IsClone, NewCreatedByUserId, NewCreatedDate, NewUpdatedByUserId, NewUpdatedDate)
OUTPUT tblSource.[OldFormSectionInstanceId], INSERTED.FormSectionInstanceId
INTO #FormSectionInstanceTable(OldFormSectionInstanceId, NewFormSectionInstanceId);
-- Copy the FormDetail
INSERT INTO [dbo].[FormDetail]
(FormHeaderId, FormFieldId, FormSectionInstanceId, IsOther, Value, CreatedByUserId, CreatedDate, UpdatedByUserId, UpdatedDate)
SELECT
#NewFormHeaderId, FormFieldId, fsit.NewFormSectionInstanceId, IsOther, Value, #UserId, CreatedDate, #UserId, UpdatedDate
FROM [dbo].[FormDetail] fd
INNER JOIN #FormSectionInstanceTable fsit ON fsit.OldFormSectionInstanceId = fd.FormSectionInstanceId
WHERE [FormHeaderId] = #FormHeaderId

Here's a solution that doesn't use MERGE (which I've had problems with many times I try to avoid if possible). It relies on two memory tables (you could use temp tables if you want) with IDENTITY columns that get matched, and importantly, using ORDER BY when doing the INSERT, and WHERE conditions that match between the two INSERTs... the first one holds the source IDs and the second one holds the target IDs.
-- Setup... We have a table that we need to know the old IDs and new IDs after copying.
-- We want to copy all of DocID=1
DECLARE #newDocID int = 99;
DECLARE #tbl table (RuleID int PRIMARY KEY NOT NULL IDENTITY(1, 1), DocID int, Val varchar(100));
INSERT INTO #tbl (DocID, Val) VALUES (1, 'RuleA-2'), (1, 'RuleA-1'), (2, 'RuleB-1'), (2, 'RuleB-2'), (3, 'RuleC-1'), (1, 'RuleA-3')
-- Create a break in IDENTITY values.. just to simulate more realistic data
INSERT INTO #tbl (Val) VALUES ('DeleteMe'), ('DeleteMe');
DELETE FROM #tbl WHERE Val = 'DeleteMe';
INSERT INTO #tbl (DocID, Val) VALUES (6, 'RuleE'), (7, 'RuleF');
SELECT * FROM #tbl t;
-- Declare TWO temp tables each with an IDENTITY - one will hold the RuleID of the items we are copying, other will hold the RuleID that we create
DECLARE #input table (RID int IDENTITY(1, 1), SourceRuleID int NOT NULL, Val varchar(100));
DECLARE #output table (RID int IDENTITY(1,1), TargetRuleID int NOT NULL, Val varchar(100));
-- Capture the IDs of the rows we will be copying by inserting them into the #input table
-- Important - we must specify the sort order - best thing is to use the IDENTITY of the source table (t.RuleID) that we are copying
INSERT INTO #input (SourceRuleID, Val) SELECT t.RuleID, t.Val FROM #tbl t WHERE t.DocID = 1 ORDER BY t.RuleID;
-- Copy the rows, and use the OUTPUT clause to capture the IDs of the inserted rows.
-- Important - we must use the same WHERE and ORDER BY clauses as above
INSERT INTO #tbl (DocID, Val)
OUTPUT Inserted.RuleID, Inserted.Val INTO #output(TargetRuleID, Val)
SELECT #newDocID, t.Val FROM #tbl t
WHERE t.DocID = 1
ORDER BY t.RuleID;
-- Now #input and #output should have the same # of rows, and the order of both inserts was the same, so the IDENTITY columns (RID) can be matched
-- Use this as the map from old-to-new when you are copying sub-table rows
-- Technically, #input and #output don't even need the 'Val' columns, just RID and RuleID - they were included here to prove that the rules matched
SELECT i.*, o.* FROM #output o
INNER JOIN #input i ON i.RID = o.RID
-- Confirm the matching worked
SELECT * FROM #tbl t

Updating Values of a table from same table without using a select query

My Requirement
Updating Values of a table from same table without using a select query
this query won't effect any rows.
My aim : Update val2 of #table where slno=1 with the value of val2 of slno=2
Is there any other way without doing this method
Declare #val2 nvarchar(50)
select #val2=val2 from #table where slno=2
update #table set val2=#val2 where slno=1
create table #table
(
slno int identity(1,1),
val nvarchar(50),
val2 nvarchar(50)
)
insert into #table(val,val2)values('1',newID())
insert into #table(val,val2)values('1',newID())
insert into #table(val,val2)values('1',newID())
select * from #table
update #table set val2=T.val2
from #table T where slno=1 and T.slno=2
drop table #table
I have lot of records in the table.
So If i am selecting and update it may effect the performance.

Please, provide more info.
Do you have only 2 rows in your table?
Why do you need this kind of update?
I suppose, that your db structure is wrong, but I can't tell exactly, until you explain why do you need this.
Anyway I can suggest a poor way to do this without using select. You can self join the table. It would be better to have addition column, but if you don't have it, how's you should do
UPDATE T1
SET T1.val2 = T2.val2
FROM #table T1 INNER JOIN #table T2
ON T1.slno = 1 AND T2.slno = 2

SQL Server SELECT into existing table

I am trying to select some fields from one table and insert them into an existing table from a stored procedure. Here is what I am trying:
SELECT col1, col2
INTO dbo.TableTwo
FROM dbo.TableOne
WHERE col3 LIKE #search_key
I think SELECT ... INTO ... is for temporary tables which is why I get an error that dbo.TableTwo already exists.
How can I insert multiple rows from dbo.TableOne into dbo.TableTwo?

SELECT ... INTO ... only works if the table specified in the INTO clause does not exist - otherwise, you have to use:
INSERT INTO dbo.TABLETWO
SELECT col1, col2
FROM dbo.TABLEONE
WHERE col3 LIKE #search_key
This assumes there's only two columns in dbo.TABLETWO - you need to specify the columns otherwise:
INSERT INTO dbo.TABLETWO
(col1, col2)
SELECT col1, col2
FROM dbo.TABLEONE
WHERE col3 LIKE #search_key

There are two different ways to implement inserting data from one table to another table.
For Existing Table - INSERT INTO SELECT
This method is used when the table is already created in the database earlier and the data is to be inserted into this table from another table. If columns listed in insert clause and select clause are same, they are not required to list them. It is good practice to always list them for readability and scalability purpose.
----Create testable
CREATE TABLE TestTable (FirstName VARCHAR(100), LastName VARCHAR(100))
----INSERT INTO TestTable using SELECT
INSERT INTO TestTable (FirstName, LastName)
SELECT FirstName, LastName
FROM Person.Contact
WHERE EmailPromotion = 2
----Verify that Data in TestTable
SELECT FirstName, LastName
FROM TestTable
----Clean Up Database
DROP TABLE TestTable
For Non-Existing Table - SELECT INTO
This method is used when the table is not created earlier and needs to be created when data from one table is to be inserted into the newly created table from another table. The new table is created with the same data types as selected columns.
----Create a new table and insert into table using SELECT INSERT
SELECT FirstName, LastName
INTO TestTable
FROM Person.Contact
WHERE EmailPromotion = 2
----Verify that Data in TestTable
SELECT FirstName, LastName
FROM TestTable
----Clean Up Database
DROP TABLE TestTable
Ref 1 2

It would work as given below :
insert into Gengl_Del Select Tdate,DocNo,Book,GlCode,OpGlcode,Amt,Narration
from Gengl where BOOK='" & lblBook.Caption & "' AND DocNO=" & txtVno.Text & ""

If the destination table does exist but you don't want to specify column names:
DECLARE #COLUMN_LIST NVARCHAR(MAX);
DECLARE #SQL_INSERT NVARCHAR(MAX);
SET #COLUMN_LIST = (SELECT DISTINCT
SUBSTRING(
(
SELECT ', table1.' + SYSCOL1.name AS [text()]
FROM sys.columns SYSCOL1
WHERE SYSCOL1.object_id = SYSCOL2.object_id and SYSCOL1.is_identity <> 1
ORDER BY SYSCOL1.object_id
FOR XML PATH ('')
), 2, 1000)
FROM
sys.columns SYSCOL2
WHERE
SYSCOL2.object_id = object_id('dbo.TableOne') )
SET #SQL_INSERT = 'INSERT INTO dbo.TableTwo SELECT ' + #COLUMN_LIST + ' FROM dbo.TableOne table1 WHERE col3 LIKE ' + #search_key
EXEC sp_executesql #SQL_INSERT

select *
into existing table database..existingtable
from database..othertables....
If you have used select * into tablename from other tablenames already, next time, to append, you say select * into existing table tablename from other tablenames

IF you want a identity column in new table created with select into then it can be done as below.
SELECT
ID = IDENTITY(INT, 1, 1),
name
INTO table2
FROM table1

If you want to insert into Table_A, from Table_B, only if the column is not in Table_A, then use the following:
BEGIN TRANSACTION
INSERT INTO dbo.Table_A (Column_1)
SELECT DISTINCT Some_Column AS Column_1
FROM dbo.Table_B
WHERE Some_Column
NOT IN (SELECT DISTINCT GroupId
FROM dbo.Table_A)
COMMIT

How do I do an Upsert Into Table?

I have a view that has a list of jobs in it, with data like who they're assigned to and the stage they are in. I need to write a stored procedure that returns how many jobs each person has at each stage.
So far I have this (simplified):
DECLARE #ResultTable table
(
StaffName nvarchar(100),
Stage1Count int,
Stage2Count int
)
INSERT INTO #ResultTable (StaffName, Stage1Count)
SELECT StaffName, COUNT(*) FROM ViewJob
WHERE InStage1 = 1
GROUP BY StaffName
INSERT INTO #ResultTable (StaffName, Stage2Count)
SELECT StaffName, COUNT(*) FROM ViewJob
WHERE InStage2 = 1
GROUP BY StaffName
The problem with that is that the rows don't combine. So if a staff member has jobs in stage1 and stage2 there's two rows in #ResultTable. What I would really like to do is to update the row if one exists for the staff member and insert a new row if one doesn't exist.
Does anyone know how to do this, or can suggest a different approach?
I would really like to avoid using cursors to iterate on the list of users (but that's my fall back option).
I'm using SQL Server 2005.
Edit: #Lee: Unfortunately the InStage1 = 1 was a simplification. It's really more like WHERE DateStarted IS NOT NULL and DateFinished IS NULL.
Edit: #BCS: I like the idea of doing an insert of all the staff first so I just have to do an update every time. But I'm struggling to get those UPDATE statements correct.

Actually, I think you're making it much harder than it is. Won't this code work for what you're trying to do?
SELECT StaffName, SUM(InStage1) AS 'JobsAtStage1', SUM(InStage2) AS 'JobsAtStage2'
FROM ViewJob
GROUP BY StaffName

You could just check for existence and use the appropriate command. I believe this really does use a cursor behind the scenes, but it's the best you'll likely get:
IF (EXISTS (SELECT * FROM MyTable WHERE StaffName = #StaffName))
begin
UPDATE MyTable SET ... WHERE StaffName = #StaffName
end
else
begin
INSERT MyTable ...
end
SQL2008 has a new MERGE capability which is cool, but it's not in 2005.

IIRC there is some sort of "On Duplicate" (name might be wrong) syntax that lets you update if a row exists (MySQL)
Alternately some form of:
INSERT INTO #ResultTable (StaffName, Stage1Count, Stage2Count)
SELECT StaffName,0,0 FROM ViewJob
GROUP BY StaffName
UPDATE #ResultTable Stage1Count= (
SELECT COUNT(*) AS count FROM ViewJob
WHERE InStage1 = 1
#ResultTable.StaffName = StaffName)
UPDATE #ResultTable Stage2Count= (
SELECT COUNT(*) AS count FROM ViewJob
WHERE InStage2 = 1
#ResultTable.StaffName = StaffName)

To get a real "upsert" type of query you need to use an if exists... type of thing, and this unfortunately means using a cursor.
However, you could run two queries, one to do your updates where there is an existing row, then afterwards insert the new one. I'd think this set-based approach would be preferable unless you're dealing exclusively with small numbers of rows.

The following query on your result table should combine the rows again. This is assuming that InStage1 and InStage2 are never both '1'.
select distinct(rt1.StaffName), rt2.Stage1Count, rt3.Stage2Count
from #ResultTable rt1
left join #ResultTable rt2 on rt1.StaffName=rt2.StaffName and rt2.Stage1Count is not null
left join #ResultTable rt3 on rt1.StaffName=rt2.StaffName and rt3.Stage2Count is not null

I managed to get it working with a variation of BCS's answer. It wouldn't let me use a table variable though, so I had to make a temp table.
CREATE TABLE #ResultTable
(
StaffName nvarchar(100),
Stage1Count int,
Stage2Count int
)
INSERT INTO #ResultTable (StaffName)
SELECT StaffName FROM ViewJob
GROUP BY StaffName
UPDATE #ResultTable SET
Stage1Count= (
SELECT COUNT(*) FROM ViewJob V
WHERE InStage1 = 1 AND
V.StaffName = #ResultTable.StaffName COLLATE Latin1_General_CI_AS
GROUP BY V.StaffName),
Stage2Count= (
SELECT COUNT(*) FROM ViewJob V
WHERE InStage2 = 1 AND
V.StaffName = #ResultTable.StaffName COLLATE Latin1_General_CI_AS
GROUP BY V.StaffName)
SELECT StaffName, Stage1Count, Stage2Count FROM #ResultTable
DROP TABLE #ResultTable

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