Support Guid ToString in SqLite, add test for mssql and sqlite

[jogibear9988]

Fix #4295

[jogibear9988]

Should I add "Guid.ToString" in Expressions.cs and create a Builder wich does nothing in Standard and in Sqlite I implement the logic. Same as I've done for TimeSpan in this: https://github.com/linq2db/linq2db/pull/3994/files#diff-0381ba7e238d0f1809d47075f54b06e6c5fb0dfd9c7f0ed1017188c0eab15e38
Would this be a better solution?

[MaceWindu]

I'm a bit lost here. What you need to achieve? If you need guid.ToString mapping to SQL you should implement it in mappings (Expressions.cs probably).

Another thing that looks incorrect is that proposed mapping generates upper-case guid. It is common to use lowercased guid string and default mapping should generate lowercased guid.

[jogibear9988]

I'm a bit lost here. What you need to achieve? If you need guid.ToString mapping to SQL you should implement it in mappings (Expressions.cs probably).

Another thing that looks incorrect is that proposed mapping generates upper-case guid. It is common to use lowercased guid string and default mapping should generate lowercased guid.

I'd like to be able to use for example guid.ToString().Contains("aa") in LINQ.
I can change to a lowercase. And I look to move to expressions

[igor-tkachev]

We already have it for other types. See Expressions.cs line 555.

[jogibear9988]

@igor-tkachev
changed code to use expression.cs and a converter in Sql Helper class

[jogibear9988]

/azp run test-all

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[linq2dbot]

Test baselines changed by this PR. Don't forget to merge/close baselines PR after this pr merged/closed.

[jogibear9988]

/azp run test-all

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[jogibear9988]

The test 3791 does not work for ClickHouse with this change

ClickHouse.Client.ClickHouseServerException : Code: 53. DB::Exception: Can't infer common type for joined columns: OtherId: Nullable(String) at left, a_Association.Id: UUID at right. There is no supertype for types String, UUID because some of them are String/FixedString and some of them are not. (TYPE_MISMATCH) (version 23.12.2.59 (official build))

	public void Issue3791Test([DataSources] string context)
	{
		var ms = new MappingSchema();
		ms.SetConvertExpression<Guid, string>(a => a.ToString());
		ms.SetConvertExpression<string, Guid>(a => Guid.Parse(a));

		using var db = GetDataContext(context);

		using var table = db.CreateLocalTable<Issue3791Table>();
		using var _     = db.CreateLocalTable<Issue3791GuidTable>();

		table.LoadWith(a => a.Association).ToList();
	}

but for me it's not clear, when the convertExpression is used. Do I need to change smth. or need this to be fixed inside of linq2db?

[jogibear9988]

Is the ms.SetConvertExpression<Guid, string> used before my handling of ToSting in Expressions.cs?

[jogibear9988]

/azp run test-all

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[jogibear9988]

/azp run test-all

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Azure Pipelines successfully started running 1 pipeline(s).

[jogibear9988]

/azp run test-all

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Azure Pipelines successfully started running 1 pipeline(s).

[linq2dbot]

Test baselines changed by this PR. Don't forget to merge/close baselines PR after this pr merged/closed.

[jogibear9988]

all tests work, ready for review

[viceroypenguin]

/azp run test-all

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Azure Pipelines successfully started running 1 pipeline(s).

[jogibear9988]

1 test failed, but it's unrelated to the pull req, cause the Code from the pull req is only used in the new test...