Handle MySQL/MariaDB DELETE with self-referencing subquery limitation

[Copilot]

MySQL and MariaDB < 11.0 throw error 1093 "You can't specify target table for update in FROM clause" when executing DELETE statements that reference the target table in a subquery. MariaDB 11.0+ lifted this limitation. UPDATE statements behave differently: they fail on MySQL but work on all MariaDB versions.

Changes

• Added DeleteWithSelfReferencingSubquery server capability flag

  • MySqlServerVersion: always false
  • MariaDbServerVersion: true for version >= 11.0.0

• Updated DELETE tests to conditionally expect MySqlException

  • Delete_with_LeftJoin
  • Delete_with_LeftJoin_via_flattened_GroupJoin
  • Delete_GroupBy_Where_Select_First_3 (multiple test classes)

• Preserved UPDATE test behavior

  • Update_Where_GroupBy_First_set_constant_3 continues checking ServerType.MySql since UPDATE works on all MariaDB versions

Example

public override async Task Delete_with_LeftJoin(bool async)
{
    if (!AppConfig.ServerVersion.Supports.DeleteWithSelfReferencingSubquery)
    {
        // MySQL and MariaDB < 11.0
        await Assert.ThrowsAsync<MySqlException>(
            () => base.Delete_with_LeftJoin(async));
    }
    else
    {
        // MariaDB >= 11.0
        await base.Delete_with_LeftJoin(async);
    }
}

Tests now pass on MySQL 8.0.40, MariaDB 10.5.27, and MariaDB 11.6.2.

Original prompt

---

This section details on the original issue you should resolve

<issue_title>You can't specify target table 'o' for update in FROM clause</issue_title>
<issue_description>With respect to the difference in MySQL and Mariadb, this is broken for MySQL v8.0.40, MariaDB 10.5.27, but it works in MariaDB 11.6.2:

  Failed Pomelo.EntityFrameworkCore.MySql.FunctionalTests.BulkUpdates.NorthwindBulkUpdatesMySqlTest.Delete_with_LeftJoin(async: False) [161 ms]
  Error Message:
   MySqlConnector.MySqlException : You can't specify target table 'o' for update in FROM clause
  Stack Trace:
     at MySqlConnector.Core.ServerSession.ReceiveReplyAsync(IOBehavior ioBehavior, CancellationToken cancellationToken) in /_/src/MySqlConnector/Core/ServerSession.cs:line 1125
   at MySqlConnector.Core.ResultSet.ReadResultSetHeaderAsync(IOBehavior ioBehavior) in /_/src/MySqlConnector/Core/ResultSet.cs:line 37
   at MySqlConnector.MySqlDataReader.ActivateResultSet(CancellationToken cancellationToken) in /_/src/MySqlConnector/MySqlDataReader.cs:line 133
   at MySqlConnector.MySqlDataReader.InitAsync(CommandListPosition commandListPosition, ICommandPayloadCreator payloadCreator, IDictionary`2 cachedProcedures, IMySqlCommand command, CommandBehavior behavior, Activity activity, IOBehavior ioBehavior, CancellationToken cancellationToken) in /_/src/MySqlConnector/MySqlDataReader.cs:line 489
   at MySqlConnector.Core.CommandExecutor.ExecuteReaderAsync(CommandListPosition commandListPosition, ICommandPayloadCreator payloadCreator, CommandBehavior behavior, Activity activity, IOBehavior ioBehavior, CancellationToken cancellationToken) in /_/src/MySqlConnector/Core/CommandExecutor.cs:line 58
   at MySqlConnector.MySqlCommand.ExecuteNonQueryAsync(IOBehavior ioBehavior, CancellationToken cancellationToken) in /_/src/MySqlConnector/MySqlCommand.cs:line 304
   at MySqlConnector.MySqlCommand.ExecuteNonQuery() in /_/src/MySqlConnector/MySqlCommand.cs:line 108
   at Microsoft.EntityFrameworkCore.Storage.RelationalCommand.ExecuteNonQuery(RelationalCommandParameterObject parameterObject)
   at Microsoft.EntityFrameworkCore.Query.RelationalShapedQueryCompilingExpressionVisitor.<>c.<NonQueryResult>b__30_0(DbContext _, ValueTuple`3 state)
   at Microsoft.EntityFrameworkCore.Storage.ExecutionStrategy.Execute[TState,TResult](TState state, Func`3 operation, Func`3 verifySucceeded)
   at Microsoft.EntityFrameworkCore.Query.RelationalShapedQueryCompilingExpressionVisitor.NonQueryResult(RelationalQueryContext relationalQueryContext, RelationalCommandResolver relationalCommandResolver, Type contextType, CommandSource commandSource, Boolean threadSafetyChecksEnabled)
   at Microsoft.EntityFrameworkCore.Query.Internal.QueryCompiler.ExecuteCore[TResult](Expression query, Boolean async, CancellationToken cancellationToken)
   at Microsoft.EntityFrameworkCore.Query.Internal.QueryCompiler.Execute[TResult](Expression query)
   at Microsoft.EntityFrameworkCore.Query.Internal.EntityQueryProvider.Execute[TResult](Expression expression)
   at Microsoft.EntityFrameworkCore.EntityFrameworkQueryableExtensions.ExecuteDelete[TSource](IQueryable`1 source)
   at Microsoft.EntityFrameworkCore.TestUtilities.BulkUpdatesAsserter.<>c__DisplayClass6_0`1.<<AssertDelete>b__0>d.MoveNext()
--- End of stack trace from previous location ---
   at Microsoft.EntityFrameworkCore.TestUtilities.TestHelpers.<>c__DisplayClass41_0`1.<<ExecuteWithStrategyInTransactionAsync>b__0>d.MoveNext()
--- End of stack trace from previous location ---
   at Microsoft.EntityFrameworkCore.ExecutionStrategyExtensions.<>c__7`1.<<ExecuteAsync>b__7_0>d.MoveNext()
--- End of stack trace from previous location ---
   at Microsoft.EntityFrameworkCore.Storage.ExecutionStrategy.<>c__DisplayClass30_0`2.<<ExecuteAsync>b__0>d.MoveNext()
--- End of stack trace from previous location ---
   at Microsoft.EntityFrameworkCore.Storage.ExecutionStrategy.ExecuteImplementationAsync[TState,TResult](Func`4 operation, Func`4 verifySucceeded, TState state, CancellationToken cancellationToken)
   at Microsoft.EntityFrameworkCore.Storage.ExecutionStrategy.ExecuteImplementationAsync[TState,TResult](Func`4 operation, Func`4 verifySucceeded, TState state, CancellationToken cancellationToken)
   at Microsoft.EntityFrameworkCore.Storage.ExecutionStrategy.ExecuteAsync[TState,TResult](TState state, Func`4 operation, Func`4 verifySucceeded, CancellationToken cancellationToken)
   at Microsoft.EntityFrameworkCore.TestUtilities.TestHelpers.ExecuteWithStrategyInTransactionAsync[TContext](Func`1 createContext, Action`2 useTransaction, Func`2 testOperation, Func`2 nestedTestOperation1, Func`2 nestedTestOperation2, Func`2 nestedTestOperation3)
   at Pomelo.EntityFrameworkCore.MySql.FunctionalTests.BulkUpdates.NorthwindBulkUpdatesMySqlTest.Delete_with_LeftJoin(Boolean async) in /home/runner/work/Pomelo.EntityFrameworkCore.MySql/Pomelo.EntityFrameworkCore.MySql/test/EFCore.MySql.FunctionalTests/BulkUpdates/NorthwindBulkUpdatesMySqlTest.cs:line 5...

</details>



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- Fixes microting/Pomelo.EntityFrameworkCore.MySql#212

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[renemadsen]

@copilot This is related I guess:

Failed Pomelo.EntityFrameworkCore.MySql.FunctionalTests.BulkUpdates.NonSharedModelBulkUpdatesMySqlTest.Delete_predicate_based_on_optional_navigation(async: False) [3 s]
Error Message:
MySqlConnector.MySqlException : You can't specify target table 'p' for update in FROM clause
Stack Trace:
at MySqlConnector.Core.ServerSession.ReceiveReplyAsync(IOBehavior ioBehavior, CancellationToken cancellationToken) in //src/MySqlConnector/Core/ServerSession.cs:line 1125
at MySqlConnector.Core.ResultSet.ReadResultSetHeaderAsync(IOBehavior ioBehavior) in //src/MySqlConnector/Core/ResultSet.cs:line 37
at MySqlConnector.MySqlDataReader.ActivateResultSet(CancellationToken cancellationToken) in /_/src/MySqlConnector/MySqlDataReader.cs:line 133
at MySqlConnector.MySqlDataReader.InitAsync(CommandListPosition commandListPosition, ICommandPayloadCreator payloadCreator, IDictionary2 cachedProcedures, IMySqlCommand command, CommandBehavior behavior, Activity activity, IOBehavior ioBehavior, CancellationToken cancellationToken) in /_/src/MySqlConnector/MySqlDataReader.cs:line 489 at MySqlConnector.Core.CommandExecutor.ExecuteReaderAsync(CommandListPosition commandListPosition, ICommandPayloadCreator payloadCreator, CommandBehavior behavior, Activity activity, IOBehavior ioBehavior, CancellationToken cancellationToken) in /_/src/MySqlConnector/Core/CommandExecutor.cs:line 58 at MySqlConnector.MySqlCommand.ExecuteNonQueryAsync(IOBehavior ioBehavior, CancellationToken cancellationToken) in /_/src/MySqlConnector/MySqlCommand.cs:line 304 at MySqlConnector.MySqlCommand.ExecuteNonQuery() in /_/src/MySqlConnector/MySqlCommand.cs:line 108 at Microsoft.EntityFrameworkCore.Storage.RelationalCommand.ExecuteNonQuery(RelationalCommandParameterObject parameterObject) at Microsoft.EntityFrameworkCore.Query.RelationalShapedQueryCompilingExpressionVisitor.<>c.<NonQueryResult>b__30_0(DbContext _, ValueTuple3 state)
at Microsoft.EntityFrameworkCore.Storage.ExecutionStrategy.Execute[TState,TResult](TState state, Func3 operation, Func3 verifySucceeded)
at Microsoft.EntityFrameworkCore.Query.RelationalShapedQueryCompilingExpressionVisitor.NonQueryResult(RelationalQueryContext relationalQueryContext, RelationalCommandResolver relationalCommandResolver, Type contextType, CommandSource commandSource, Boolean threadSafetyChecksEnabled)
at Microsoft.EntityFrameworkCore.Query.Internal.QueryCompiler.ExecuteCore[TResult](Expression query, Boolean async, CancellationToken cancellationToken)
at Microsoft.EntityFrameworkCore.Query.Internal.QueryCompiler.Execute[TResult](Expression query)
at Microsoft.EntityFrameworkCore.Query.Internal.EntityQueryProvider.Execute[TResult](Expression expression)
at Microsoft.EntityFrameworkCore.EntityFrameworkQueryableExtensions.ExecuteDelete[TSource](IQueryable1 source) at Microsoft.EntityFrameworkCore.BulkUpdates.NonSharedModelBulkUpdatesTestBase.<>c__DisplayClass28_02.<b__0>d.MoveNext()
--- End of stack trace from previous location ---
at Microsoft.EntityFrameworkCore.TestUtilities.TestHelpers.<>c__DisplayClass41_01.<<ExecuteWithStrategyInTransactionAsync>b__0>d.MoveNext() --- End of stack trace from previous location --- at Microsoft.EntityFrameworkCore.ExecutionStrategyExtensions.<>c__71.<b__7_0>d.MoveNext()
--- End of stack trace from previous location ---
at Microsoft.EntityFrameworkCore.Storage.ExecutionStrategy.<>c__DisplayClass30_02.<<ExecuteAsync>b__0>d.MoveNext() --- End of stack trace from previous location --- at Microsoft.EntityFrameworkCore.Storage.ExecutionStrategy.ExecuteImplementationAsync[TState,TResult](Func4 operation, Func4 verifySucceeded, TState state, CancellationToken cancellationToken) at Microsoft.EntityFrameworkCore.Storage.ExecutionStrategy.ExecuteImplementationAsync[TState,TResult](Func4 operation, Func4 verifySucceeded, TState state, CancellationToken cancellationToken) at Microsoft.EntityFrameworkCore.Storage.ExecutionStrategy.ExecuteAsync[TState,TResult](TState state, Func4 operation, Func4 verifySucceeded, CancellationToken cancellationToken) at Microsoft.EntityFrameworkCore.TestUtilities.TestHelpers.ExecuteWithStrategyInTransactionAsync[TContext](Func1 createContext, Action2 useTransaction, Func2 testOperation, Func2 nestedTestOperation1, Func2 nestedTestOperation2, Func`2 nestedTestOperation3)
at Microsoft.EntityFrameworkCore.BulkUpdates.NonSharedModelBulkUpdatesTestBase.Delete_predicate_based_on_optional_navigation(Boolean async)
at Pomelo.EntityFrameworkCore.MySql.FunctionalTests.BulkUpdates.NonSharedModelBulkUpdatesMySqlTest.Delete_predicate_based_on_optional_navigation(Boolean async) in /home/runner/work/Pomelo.EntityFrameworkCore.MySql/Pomelo.EntityFrameworkCore.MySql/test/EFCore.MySql.FunctionalTests/BulkUpdates/NonSharedModelBulkUpdatesMySqlTest.cs:line 56
--- End of stack trace from previous location ---