[release/7.0] Use correct parameter in query based on type mapping #29724
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Fixes #29646, backports #29650
Description
When the same parameter is used in a query in contexts which require different type mappings, we sometimes use the incorrect type mapping in the incorrect context.
Customer impact
Since the incorrect SQL representation or parameter may be sent to the server, LINQ queries may return incorrect data. For example, if the same .NET string is compared against both Unicode and non-Unicode database columns in a query, that could yield wrong results.
How found
Customer reported on 7.0
Regression
Yes.
Testing
Added a test for the affected scenario.
Risk
Low; the fix is quite trivial, and a quirk was added to revert back to older behavior.