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Remove MySQL support

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This commit is contained in:
Sebastiaan Janssen
2019-01-17 12:07:31 +01:00
parent cdf38af171
commit 9e7eb2ad75
49 changed files with 600 additions and 2388 deletions
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28
src/Umbraco.Core/Persistence/NPocoDatabaseExtensions.cs
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@@ -32,30 +32,6 @@ namespace Umbraco.Core.Persistence
//
// works in READ COMMITED, TSQL & SQLCE lock the constraint even if it does not exist, so INSERT is OK
//
// proper way to do it with MySQL
// IF EXISTS (SELECT ... FROM table WHERE ... FOR UPDATE)
// BEGIN
// UPDATE table SET ... WHERE ...
// END
// ELSE
// BEGIN
// INSERT INTO table (...) VALUES (...)
// END
//
// MySQL locks the constraint ONLY if it exists, so INSERT may fail...
// in theory, happens in READ COMMITTED but not REPEATABLE READ
// http://www.percona.com/blog/2012/08/28/differences-between-read-committed-and-repeatable-read-transaction-isolation-levels/
// but according to
// http://dev.mysql.com/doc/refman/5.0/en/set-transaction.html
// it won't work for exact index value (only ranges) so really...
//
// MySQL should do
// INSERT INTO table (...) VALUES (...) ON DUPLICATE KEY UPDATE ...
//
// also the lock is released when the transaction is committed
// not sure if that can have unexpected consequences on our code?
//
// so... for the time being, let's do with that somewhat crazy solution below...
// todo: use the proper database syntax, not this kludge
/// <summary>
@@ -66,7 +42,7 @@ namespace Umbraco.Core.Persistence
/// <returns>The action that executed, either an insert or an update. If an insert occurred and a PK value got generated, the poco object
/// passed in will contain the updated value.</returns>
/// <remarks>
/// <para>We cannot rely on database-specific options such as MySql ON DUPLICATE KEY UPDATE or MSSQL MERGE WHEN MATCHED because SQLCE
/// <para>We cannot rely on database-specific options because SQLCE
/// does not support any of them. Ideally this should be achieved with proper transaction isolation levels but that would mean revisiting
/// isolation levels globally. We want to keep it simple for the time being and manage it manually.</para>
/// <para>We handle it by trying to update, then insert, etc. until something works, or we get bored.</para>
@@ -89,7 +65,7 @@ namespace Umbraco.Core.Persistence
/// <returns>The action that executed, either an insert or an update. If an insert occurred and a PK value got generated, the poco object
/// passed in will contain the updated value.</returns>
/// <remarks>
/// <para>We cannot rely on database-specific options such as MySql ON DUPLICATE KEY UPDATE or MSSQL MERGE WHEN MATCHED because SQLCE
/// <para>We cannot rely on database-specific options because SQLCE
/// does not support any of them. Ideally this should be achieved with proper transaction isolation levels but that would mean revisiting
/// isolation levels globally. We want to keep it simple for the time being and manage it manually.</para>
/// <para>We handle it by trying to update, then insert, etc. until something works, or we get bored.</para>