If you make all the FK's ON DELETE CASCADE you can just delete small batches of rows from the Sample table. You would need indexes on the SampleID columns on...

Normally when an example is given using values A, B and C they should be taken as algebraic variables who's contents can change. More like this example:

DECLARE @A char(1), @b-2...

Alexander-449406 (6/6/2014)

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I have generated test data with 1 000 000 000 000 000 000 000 rows and according to my tests all the queries proposed run within 1 second. You...

This script may be ok to use on some occasions but if the entry of the parameters is from an external input, e.g. a web page, then it could be...

Or this:

;WITH CTE AS

(

SELECT E.Company,

E.Employee,

...

I think simply testing for existence should do what you need.

SELECT E.Company,

E.Employee,

E.TermDate

FROM...

Good article. Nice way of selecting all columns when detecting duplicates for a subset of the columns.

So this is your homework?

Is there a maximum number of distinct serial numbers or are there at most 7 like in your example?

I think this might be what you need:

;WITH CTE AS

(

SELECT DISTINCT

SerialBox

...

I just tried it on a bit of xml that had a DataLength of 13859 and it took 3:28 (3 minutes 28 seconds) to complete. I then tried it on...

I tried running it on a bit of xml that stores an order on our database.

It ran for over 6 minutes before I stopped it.

Using a cursor:

DECLARE myCursor cursor LOCAL FORWARD_ONLY FAST_FORWARD READ_ONLY

FOR SELECT OfficeId

FROM dbo.Office

DECLARE @OfficeId int,...

Or using CROSS APPLY:

SELECT OfficeID,

S.StateAbbr,

C.countrynames

FROM dbo.Office O

CROSS APPLY (SELECT TOP(1)

...

A csv list can also be generated using "FOR XML"

I rewrote the final query using this method:

SELECT OfficeID, 
       (SELECT TOP(1)
...