Address Query Parsing Performance

[jogibear9988]

Fixes #4394

[MaceWindu]

/azp run test-metrics

[azure-pipelines]

Azure Pipelines successfully started running 1 pipeline(s).

[MaceWindu]

that's in debug with overridetostrng

[MaceWindu]

and in release

[jogibear9988]

As Info: I merged #4339 in this pull request, cause without the query would not run at all.

[MaceWindu]

I doubt it makes sense to do anything here before new parser lends. Profiler shows about half of time spent in this method https://github.com/linq2db/linq2db/blob/master/Source/LinqToDB/SqlQuery/SelectQueryOptimizer.cs#L453-L482

@sdanyliv ?

[MaceWindu]

[MaceWindu]

new parser shows similar numbers currently, but as I said - it's better leave it for later as slow areas will be heavy refactored there

[linq2dbot]

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

[igor-tkachev]

I like this test. Profiler shows a lot of points to optimize.

[sdanyliv]

Profiler adds additional delays. Without profiler in Release, whole query is executed under 550-600 milliseconds. Second run with cache hit is 8 msec. There are a lot of ways how to improve SelectQuery optimization and I will make research for new LINQ Translator but after all tests are passed. Not too much left.

Note that SelectQuery optimization is fully REWRITTEN, making cardinal changes in current version will be discarded .

[jogibear9988]

@sdanyliv

Your coments were already resolved in pull req for issue #4337, wich I had merged into this, without this the query didn't run at all

[jogibear9988]

The Test results in an endless call stack of this 4 methods, till it crashes...

[sdanyliv]

Remove that

[sdanyliv]

Tested on V6
In Release second query executes approx 8 seconds without Stack Overflow. In Debug it crashes with SO, Probably too much debug information

Good test for optimizing translator, bad for production.

Your goal to kill linq2db or make job done?

[jogibear9988]

Tested on V6 In Release second query executes approx 8 seconds without Stack Overflow. In Debug it crashes with SO, Probably too much debug information

Good test for optimizing translator, bad for production.

Your goal to kill linq2db or make job done?

I tried in Release mode....

I did not write this query, also in out software it was only for 3Shelfs, now someone needed it for 10...
the Performance is not really very critical, so if it works, it does not matter.

But for now, we created a view wich we map to the same object.