Fix to #18808 - Query: incorrect results for query with Join where key selector is anonymous type with a single property #18810
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maumar
commented
Nov 7, 2019
| INNER JOIN [LevelTwo] AS [l2] ON ([l1].[OneToMany_Optional_Self_Inverse1Id] = [l2].[Level1_Optional_Id]) OR ([l1].[OneToMany_Optional_Self_Inverse1Id] IS NULL AND [l2].[Level1_Optional_Id] IS NULL)"); | ||
| @"SELECT [l].[Id], [l].[Date], [l].[Name], [l].[OneToMany_Optional_Self_Inverse1Id], [l].[OneToMany_Required_Self_Inverse1Id], [l].[OneToOne_Optional_Self1Id] | ||
| FROM [LevelOne] AS [l] | ||
| INNER JOIN [LevelTwo] AS [l0] ON (([l].[OneToMany_Optional_Self_Inverse1Id] = [l0].[Level1_Optional_Id]) OR ([l].[OneToMany_Optional_Self_Inverse1Id] IS NULL AND [l0].[Level1_Optional_Id] IS NULL)) AND (CAST(1 AS bit) = CAST(1 AS bit))"); |
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extra condition can be pruned, when/if we fix #18492
…y selector is anonymous type with a single property
Problem was that on c# join predicate behaves differently when it's a regular property (null and null yield false), and where its anonymous type with just a single property (new { A = null } and new { A = null } yields true).
However, we lose that distinction during initial Join predicate translation.
Fix is to add a sentinel true == true condition, if the anonymous type only has one element. This condition can be later optimized out.
Resolves #18808
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Problem was that on c# join predicate behaves differently when it's a regular property (null and null yield false), and where its anonymous type with just a single property (new { A = null } and new { A = null } yields true).
However, we lose that distinction during initial Join predicate translation.
Fix is to add a sentinel true == true condition, if the anonymous type only has one element. This condition can be later optimized out.
Resolves #18808