Delete Strategy vs. Rollback Strategy - ETL Download

Question

I load the data into a table as follows:

DECLARE @srcRc INT;
DECLARE @dstRc INT;

SET @srcRc = ( SELECT COUNT(*) FROM A )

INSERT  INTO t
        (Col1
        ,Col2
        ,Col3
        )
        SELECT  A.Col1
               ,A.Col2
               ,B.Col3
        FROM    A
                JOIN B
                    ON A.Id = B.Id;

SET @dstRc = @@ROWCOUNT

Now I am comparing the variables @srcRcand @dstRc. The value ROWCOUNTmust be the same. If this is not the case, the inserted rows must be deleted.

Q1: What would be the best strategy to roll back inserted rows?

I have a couple of ideas:

1) , .
2) () toBeDeleted, , toBeDeleted 1, . (while-loop).
, t.
3) , . , .

DECLARE @srcRc INT;
DECLARE @dstRc INT;
SET @srcRc = ( SELECT   COUNT(1) FROM A );
SET @dstRc = ( SELECT   COUNT(1) FROM A JOIN B ON A.Id = B.Id );

Q2: , , 10-100 .?
Q3: ?

Answer 1

, :

, A B

T , .

, A B, T

.

• , , , , .

• T [importId],

, . , , .

- sql , sql.

, ..

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Edit:

, . - .

. , , .