How can I make my database orderly after deleting exam questions in C # windows form

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Good day please I am creating a cbt app, anything I delete a question and insert another question it id does not decrease. Example, I have 10 questions after deleting it I expect the next questions I insert should start from 1 but it start from 11. Please help

What I have tried:

I have searched through the net but no answer

Posted 22-Sep-17 16:06pm

akinwunmi

Updated 22-Sep-17 20:01pm

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PIEBALDconsult 22-Sep-17 22:17pm

0) Don't delete.
1) Don't use Identity/autoincrement.

Dave Kreskowiak 22-Sep-17 22:35pm

If you're using identity or autoincrement as something to maintain order of items, you're not doing this correctly. Ordering of items should be a separate field as an integer or something appropriate.

Autoincrement ID values do NOT get recycled and reused.

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OriginalGriff · Answer 1 · 2017-09-22T19:39:00

From your description, you are using an IDENTITY column - that is the expected behaviour, and it is actually what you want to happen. The problem is that you are assuming that ir represents a row numbering system, when it represents a unique ID value for each row instead.

The database doesn't "recycle" IDENTITY values, because it doesn't "know" what you are using them for - so it assumes that you are referring to those values from other places and other data. If it recycled them, then the old data would effectively become attached to the new rows, and that could be very bad indeed. Imagine an invoicing system where purchases for a different, deleted, customer became attached to your new customer and your were charged for them!

While it is possible to reset an identity field:

SQL

DBCC CHECKIDENT('mYTable', RESEED, 1)

It's a bad idea, generally.

So don't use it as a row number: instead, use ROW_NUMBER:

SQL

SELECT ROW_NUMBER() OVER (ORDER BY ID ASC) AS RowNumber, ID, QuestionText FROM MyTable