Query: incorrect results for complex predicate with bitwise AND operation with bool args

[maumar]

query:

from o1 in context.Set<OperatorEntityString>()
from o2 in context.Set<OperatorEntityString>()
from o3 in context.Set<OperatorEntityBool>()
where ((EF.Functions.Like(o2.Value, "B") || o3.Value) & (o1.Value != null)) != false
select new { Value1 = o1.Value, Value2 = o2.Value, Value3 = o3.Value };

that predicate gets "optimized" out completely, but it's actually doing something when executed on L2O

[maumar]

problem is IsNull checks on bitwise operations with bool values are not handled correctly. On database those ops behave like regular binary, meaning if any of the values is null the result is also null. However on C# those ops behave like AndAlso/OrElse, meaning NULL & false returns false, NULL | true returns true. We can either provide proper expansions for IsNull/IsNotNull or try normalize bitwise on bool arguments into AndAlso/OrElse.

Expansions look like this:

a & b == null -> (a == null && b == null) || (a == null && b == true) || (a == true && b == null)
a | b == null -> (a == null && b == null) || (a == null && b == false) || (a == false && b == null)
a & b != null -> (a != null && b != null) || (a == null && b == false) || (a == false && b == null)
a | b != null -> (a != null && b != null) || (a == true && b == null) || (a = null && b == true)

[ranma42]

@maumar considering that the semantics for C# logical and conditional Boolean operators matches for expressions that have no side-effects, I think that for the SQL target it would be possible to always translate them as if they were conditional Boolean operators in SQL.
Do you foresee any major issue with this approach?

[ranma42]

I went forward and tried it out in

• Translate logical Boolean operators as conditional Boolean operators #33873