Untyped NULL constant value is not supported for CASE statement
Posted: Thu 23 Jan 2020 20:23
I'm getting error when DevArt attempts to build Oracle CASE statement in the query from the following .NET code:
Full stack trace:
The above error occurs when using new DevArt driver 9.10.925 with .NET Core 3.1.1/EF Core 3.1.1. However, everything works correctly when the code was running on NET Core 2.2/EF Core 2.2.6 using DevArt driver 9.9.887, so it appears that upgrading to .NET Core 3.1/EF Core 3.1 is causing this issue.
Code: Select all
System.NotImplementedException: Untyped NULL constant value is not supported.
Code: Select all
var query =
from a in some_table
let j = (a.Column1 == "0" ? a.Column1 : null) // <-- Fails because of null value!
select j;
var h = await query.FirstOrDefaultAsync();
Code: Select all
System.NotImplementedException: Untyped NULL constant value is not supported.
at Devart.Common.Entity.dc.a(SqlConstantExpression A_0)
at Microsoft.EntityFrameworkCore.Query.SqlExpressionVisitor.VisitExtension(Expression extensionExpression)
at System.Linq.Expressions.Expression.Accept(ExpressionVisitor visitor)
at Microsoft.EntityFrameworkCore.Query.QuerySqlGenerator.VisitCase(CaseExpression caseExpression)
at Microsoft.EntityFrameworkCore.Query.SqlExpressionVisitor.VisitExtension(Expression extensionExpression)
at System.Linq.Expressions.Expression.Accept(ExpressionVisitor visitor)
at Microsoft.EntityFrameworkCore.Query.QuerySqlGenerator.VisitProjection(ProjectionExpression projectionExpression)
at Microsoft.EntityFrameworkCore.Query.SqlExpressionVisitor.VisitExtension(Expression extensionExpression)
at System.Linq.Expressions.Expression.Accept(ExpressionVisitor visitor)
at Microsoft.EntityFrameworkCore.Query.QuerySqlGenerator.<VisitSelect>b__18_0(ProjectionExpression e)
at Microsoft.EntityFrameworkCore.Query.QuerySqlGenerator.GenerateList[T](IReadOnlyList`1 items, Action`1 generationAction, Action`1 joinAction)
at Microsoft.EntityFrameworkCore.Query.QuerySqlGenerator.VisitSelect(SelectExpression selectExpression)
at Devart.Common.Entity.dc.c(SelectExpression A_0)
at Devart.Data.Oracle.Entity.bg.a(SelectExpression A_0)
at Microsoft.EntityFrameworkCore.Query.QuerySqlGenerator.GetCommand(SelectExpression selectExpression)
at Devart.Common.Entity.dc.e(SelectExpression A_0)
at Microsoft.EntityFrameworkCore.Query.Internal.RelationalCommandCache.GetRelationalCommand(IReadOnlyDictionary`2 parameters)
at Microsoft.EntityFrameworkCore.Query.Internal.QueryingEnumerable`1.AsyncEnumerator.InitializeReaderAsync(DbContext _, Boolean result, CancellationToken cancellationToken)
at Microsoft.EntityFrameworkCore.Query.Internal.QueryingEnumerable`1.AsyncEnumerator.MoveNextAsync() Untyped NULL constant value is not supported.