protected override Expression VisitExtension(Expression extensionExpression)
{
// workaround for issue #18492
var newExpression = base.VisitExtension(extensionExpression);
if (newExpression is SelectExpression newSelectExpression)
{
var changed = false;
var newPredicate = newSelectExpression.Predicate;
var newHaving = newSelectExpression.Having;
if (newSelectExpression.Predicate is SqlConstantExpression predicateConstantExpression &&
predicateConstantExpression.Value is bool predicateBoolValue &&
!predicateBoolValue)
{
changed = true;
newPredicate = SqlExpressionFactory.Equal(
predicateConstantExpression,
SqlExpressionFactory.Constant(true, predicateConstantExpression.TypeMapping));
}
if (newSelectExpression.Having is SqlConstantExpression havingConstantExpression &&
havingConstantExpression.Value is bool havingBoolValue &&
!havingBoolValue)
{
changed = true;
newHaving = SqlExpressionFactory.Equal(
havingConstantExpression,
SqlExpressionFactory.Constant(true, havingConstantExpression.TypeMapping));
}
return(changed
? newSelectExpression.Update(
newSelectExpression.Projection.ToList(),
newSelectExpression.Tables.ToList(),
newPredicate,
newSelectExpression.GroupBy.ToList(),
newHaving,
newSelectExpression.Orderings.ToList(),
newSelectExpression.Limit,
newSelectExpression.Offset,
newSelectExpression.IsDistinct,
newSelectExpression.Alias)
: newSelectExpression);
}
return(newExpression);
}
protected override Expression VisitExtension(Expression extensionExpression)
{
if (extensionExpression is SelectExpression selectExpression)
{
var newSelectExpression = (SelectExpression)base.VisitExtension(extensionExpression);
// if predicate is optimized to true, we can simply remove it
var newPredicate = newSelectExpression.Predicate is SqlConstantExpression newSelectPredicateConstant &&
!(selectExpression.Predicate is SqlConstantExpression)
? (bool)newSelectPredicateConstant.Value
? null
: SqlExpressionFactory.Equal(
newSelectPredicateConstant,
SqlExpressionFactory.Constant(true, newSelectPredicateConstant.TypeMapping))
: newSelectExpression.Predicate;
var newHaving = newSelectExpression.Having is SqlConstantExpression newSelectHavingConstant &&
!(selectExpression.Having is SqlConstantExpression)
? (bool)newSelectHavingConstant.Value
? null
: SqlExpressionFactory.Equal(
newSelectHavingConstant,
SqlExpressionFactory.Constant(true, newSelectHavingConstant.TypeMapping))
: newSelectExpression.Having;
return(!ReferenceEquals(newPredicate, newSelectExpression.Predicate) ||
!ReferenceEquals(newHaving, newSelectExpression.Having)
? newSelectExpression.Update(
newSelectExpression.Projection.ToList(),
newSelectExpression.Tables.ToList(),
newPredicate,
newSelectExpression.GroupBy.ToList(),
newHaving,
newSelectExpression.Orderings.ToList(),
newSelectExpression.Limit,
newSelectExpression.Offset,
newSelectExpression.IsDistinct,
newSelectExpression.Alias)
: newSelectExpression);
}
return(base.VisitExtension(extensionExpression));
}
