Fix to #29667 - Count after Take throws "No column name was specified for column 1 of 't'." #30134
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test/EFCore.Relational.Specification.Tests/Query/KeylessEntitiesQueryAdHocTestBase.cs
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| SELECT COUNT(*) | ||
| FROM ( | ||
| SELECT TOP(@__p_0) [k].[Number] |
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Isn't it a bit odd that just adding OrderBy makes the subquery project out [Number], and when we remove it the projection disappears? I wouldn't expect OrderBy to have any effect on whether we project out or not...
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when we perform pushdown we add ordering from the subquery to the outer (so that we can order by it in the final result if needed - e.g. Correlated_collection_with_top_level_Last_with_order_by_on_inner) and in order to construct that ordering for outer we need to add it to the projection in the inner. In this case we don't end up using it, so maybe we could try prune it, but might be tricky.
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filed #30143 to track this
… for column 1 of 't'." Problem was that in some cases (e.g. count over keyless entity that has been pushed down) we now generate empty projection in the subquery, where before we were projecting some columns. SQL Server doesn't allow unaliased projection in the subquery, so the fix is to simply add an alias to the empty projection that we generate. Fixes #29667
Problem was that in some cases (e.g. count over keyless entity that has been pushed down) we now generate empty projection in the subquery, where before we were projecting some columns. SQL Server doesn't allow unaliased projection in the subquery, so the fix is to simply add an alias to the empty projection that we generate.
Fixes #29667