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c# - Unable to create a constant value of type 'System.Object' in Entity Framework

I have a table named UserTenders having many-to-one relationship with aspnet_Membership table.
I am using EntityFramework 4.0 and when I try something like this, it errors.

var tenders = ctx.UserTenders
    .Where(tender => tender.HasAdminApproved.Equals(true))
    .ToList();

The error is

System.NotSupportedException
Unable to create a constant value of type 'System.Object'.
Only primitive types ('such as Int32, String, and Guid') are supported in this context.

This snippet below works.

var tenders = ctx.UserTenders.ToList();

What could be wrong in my code? Feel like I am missing something very trivial.

I would like to filter all those rows that have the bit field HasAdminApproved as true

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1 Answer

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Try replacing

.Where(tender => tender.HasAdminApproved.Equals(true))

With:

.Where(tender => tender.HasAdminApproved == true)

Or as previously suggested by @Ladislav Mrnka if your field is bool?

.Where(tender => tender.HasAdminApproved)

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