Last Updated: 18 Mar 2020 17:40 by Kyle
Created on: 17 Mar 2020 14:19
Category: Grid
Type: Feature Request
Kendo.Mvc.Extensions.QueryableExtensions always lowers string equals

Hi guys,


I found out, that the QueryableExtension always generates a ToLower for strings filtered with the equals operator. The ToLower is applied by the FilterOperatorExtensions in this method:

    private static Expression GenerateEqual(
      Expression left,
      Expression right,
      bool liftMemberAccess)
      if (left.Type == typeof (string))
        left = FilterOperatorExtensions.GenerateToLowerCall(left, liftMemberAccess);
        right = FilterOperatorExtensions.GenerateToLowerCall(right, liftMemberAccess);
      return (Expression) Expression.Equal(left, right);

It would be nice, if the to lower is controllable with a parameter. At the moment it generates a to lower in the sql query, which generates a lot of overhead in some situations with large tables.

At the moment I remove all "equal to" filter and apply it manually to the IQueryable object.


Best regards


Posted on: 18 Mar 2020 17:40

I see where you're coming from.  And I guess, based on the COLLATION of the SQL database, it might not matter.

And this is not an argument against, just something of which to be aware:

In EF Core 3.x, string.Equals(x, y, StringComparison.OrdinalIgnoreCase) no longer works and requires us to use x.ToUpper() == y.ToUpper() (or whatever).

Angel Petrov
Posted on: 18 Mar 2020 13:23


Indeed this sounds like a reasonable requirement. I am converting the ticket to a feature request so others can vote for it.

Angel Petrov
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