Adding docs for filtered include feature and updating query samples

[maumar]

No description provided.

[maumar]

many of the filtered include scenarios translate to apply, so sqlite will throw - should we add a warning/caution for that here?

[smitpatel]

for filtered includes, take works in sqlite right?

[maumar]

Nope -

SELECT "l"."Id", "l"."Date", "l"."Name", "l"."OneToMany_Optional_Self_Inverse1Id", "l"."OneToMany_Required_Self_Inverse1Id", "l"."OneToOne_Optional_Self1Id", "t"."Id", "t"."Date", "t"."Level1_Optional_Id", "t"."Level1_Required_Id", "t"."Name", "t"."OneToMany_Optional_Inverse2Id", "t"."OneToMany_Optional_Self_Inverse2Id", "t"."OneToMany_Required_Inverse2Id", "t"."OneToMany_Required_Self_Inverse2Id", "t"."OneToOne_Optional_PK_Inverse2Id", "t"."OneToOne_Optional_Self2Id"
FROM "LevelOne" AS "l"
OUTER APPLY (
    SELECT "l0"."Id", "l0"."Date", "l0"."Level1_Optional_Id", "l0"."Level1_Required_Id", "l0"."Name", "l0"."OneToMany_Optional_Inverse2Id", "l0"."OneToMany_Optional_Self_Inverse2Id", "l0"."OneToMany_Required_Inverse2Id", "l0"."OneToMany_Required_Self_Inverse2Id", "l0"."OneToOne_Optional_PK_Inverse2Id", "l0"."OneToOne_Optional_Self2Id"
    FROM "LevelTwo" AS "l0"
    WHERE "l"."Id" = "l0"."OneToMany_Optional_Inverse2Id"
    ORDER BY "l0"."Name"
    LIMIT 3
) AS "t"
ORDER BY "l"."Id", "t"."Name", "t"."Id"

Where works, OrderBy.AsQueryable works, Skip/Take fails due to APPLY, naked OrderBy fails due to a bug

[smitpatel]

Something is wrong then. We added whole support for RowNumberExpression to convert apply to join when there is only take. dotnet/efcore#17293
There is also test which converts Take(4) in select many. At the minimum query you posted above has nothing in it which stops it from getting converted to join.

Also related to it: If we fix dotnet/efcore#17326, then skip would also convert to number and most of it should get translated to Sqlite. (For filtered include case, everything would work).

[maumar]

will investigate what's up

[maumar]

ctx.LevelOne.Select(l1 => l1.OneToMany_Optional1.OrderBy(x => x.Name).Take(3).ToList()).ToList();

still translates to apply on sqlite (and fails).

[smitpatel]

File an issue and don't add any warning here.

[maumar]

updated