Posted by Erland Sommarskog on 11/03/05 00:47

Hugo Kornelis (hugo@pe_NO_rFact.in_SPAM_fo) writes:
> The nice thing about the "old" method was that the implicit conversion
> of the constant enabled the optimizer to use an index that was defined
> on the column; in SQL Server 2000, the implicit conversion of the column
> would preclude the use of that index.

But what happened if two columns of different data types met?

> Of course, the price one paid for the index use in the old version was
> that the database didn't always do what you'd expect after perusing the
> precedence rules.

As I said, I basically slept over SQL 7, so missed the problem.

Of course, in many cases, these problems could be avoided by not
having implicit conversions at all.

--
Erland Sommarskog, SQL Server MVP, esquel@sommarskog.se

Books Online for SQL Server SP3 at
http://www.microsoft.com/sql/techinfo/productdoc/2000/books.asp

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