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Insert Update trigger how to determine if insert or update

... track "before" and "after" data. So you can use something like IF EXISTS (SELECT * FROM DELETED) to detect an update. You only have rows in DELETED on update, but there are always rows in INSERTED. Look for "inserted" in CREATE TRIGGER. Edit, 23 Nov 2011 After comment, this answer is only for INSER...
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Is there a way to loop through a table variable in TSQL without using a cursor?

...impler code. Depending on your data it may be possible to loop using just SELECT statements as shown below: Declare @Id int While (Select Count(*) From ATable Where Processed = 0) > 0 Begin Select Top 1 @Id = Id From ATable Where Processed = 0 --Do some processing here Update ATa...
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How to create Temp table with SELECT * INTO tempTable FROM CTE Query

...Time, EventRecurring Bit, EventType int ) ;WITH Calendar AS (SELECT /*...*/) Insert Into #Temp Select EventID, EventStartDate, EventEndDate, PlannedDate as [EventDates], Cast(PlannedDate As datetime) AS DT, Cast(EventStartTime As time) AS ST,Cast(EventEndTime As time) AS ET, EventTitl...
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How to get cumulative sum

the above select returns me the following. 16 Answers 16 ...
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When should I use cross apply over inner join?

...APPLY works better on things that have no simple JOIN condition. This one selects 3 last records from t2 for each record from t1: SELECT t1.*, t2o.* FROM t1 CROSS APPLY ( SELECT TOP 3 * FROM t2 WHERE t2.t1_id = t1.id ORDER BY t2.ran...
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Get the week start date and week end date from week number

...y other weird value to test it */ DECLARE @d DATETIME SET @d = GETDATE() SELECT @d ThatDate, DATEADD(dd, 0 - (@@DATEFIRST + 5 + DATEPART(dw, @d)) % 7, @d) Monday, DATEADD(dd, 6 - (@@DATEFIRST + 5 + DATEPART(dw, @d)) % 7, @d) Sunday ...
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Unknown Column In Where Clause

...om right to left. So the where clause is parsed and evaluate prior to the select clause. Because of this the aliasing of u_name to user_name has not yet occurred. share | improve this answer ...
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Postgres: INSERT if does not exist already

...onditional INSERT in PostgreSQL: INSERT INTO example_table (id, name) SELECT 1, 'John' WHERE NOT EXISTS ( SELECT id FROM example_table WHERE id = 1 ); CAVEAT This approach is not 100% reliable for concurrent write operations, though. There is a very tiny race condition between...
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How can I select multiple columns from a subquery (in SQL Server) that should have one record (selec

I Know I can select a column from a subquery using this syntax: 5 Answers 5 ...
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SQL MAX of multiple columns?

... Well, you can use the CASE statement: SELECT CASE WHEN Date1 >= Date2 AND Date1 >= Date3 THEN Date1 WHEN Date2 >= Date1 AND Date2 >= Date3 THEN Date2 WHEN Date3 >= Date1 AND Date3 >= Date2 THEN Date3 ELSE ...