private HqlTreeNode TranslateEqualityComparison(BinaryExpression expression)
{
var lhs = VisitExpression(expression.Left).ToArithmeticExpression();
var rhs = VisitExpression(expression.Right).ToArithmeticExpression();
// Check for nulls on left or right.
if (VisitorUtil.IsNullConstant(expression.Right))
{
rhs = null;
}
if (VisitorUtil.IsNullConstant(expression.Left))
{
lhs = null;
}
if (lhs == null && rhs == null)
{
return(_hqlTreeBuilder.True());
}
if (lhs == null)
{
return(_hqlTreeBuilder.IsNull(rhs));
}
if (rhs == null)
{
return(_hqlTreeBuilder.IsNull((lhs)));
}
var lhsNullable = IsNullable(lhs);
var rhsNullable = IsNullable(rhs);
var equality = _hqlTreeBuilder.Equality(lhs, rhs);
if (!lhsNullable || !rhsNullable)
{
return(equality);
}
var lhs2 = VisitExpression(expression.Left).ToArithmeticExpression();
var rhs2 = VisitExpression(expression.Right).ToArithmeticExpression();
return(_hqlTreeBuilder.BooleanOr(
equality,
_hqlTreeBuilder.BooleanAnd(
_hqlTreeBuilder.IsNull(lhs2),
_hqlTreeBuilder.IsNull(rhs2))));
}
private HqlTreeNode TranslateInequalityComparison(BinaryExpression expression)
{
var lhs = VisitExpression(expression.Left).ToArithmeticExpression();
var rhs = VisitExpression(expression.Right).ToArithmeticExpression();
// Check for nulls on left or right.
if (VisitorUtil.IsNullConstant(expression.Right))
{
rhs = null;
}
if (VisitorUtil.IsNullConstant(expression.Left))
{
lhs = null;
}
if (lhs == null && rhs == null)
{
return(_hqlTreeBuilder.False());
}
if (lhs == null)
{
return(_hqlTreeBuilder.IsNotNull(rhs));
}
if (rhs == null)
{
return(_hqlTreeBuilder.IsNotNull(lhs));
}
var lhsNullable = IsNullable(lhs);
var rhsNullable = IsNullable(rhs);
var inequality = _hqlTreeBuilder.Inequality(lhs, rhs);
if (!lhsNullable && !rhsNullable)
{
return(inequality);
}
var lhs2 = VisitExpression(expression.Left).ToArithmeticExpression();
var rhs2 = VisitExpression(expression.Right).ToArithmeticExpression();
HqlBooleanExpression booleanExpression;
if (lhsNullable && rhsNullable)
{
booleanExpression = _hqlTreeBuilder.Inequality(
_hqlTreeBuilder.IsNull(lhs2).ToArithmeticExpression(),
_hqlTreeBuilder.IsNull(rhs2).ToArithmeticExpression());
}
else if (lhsNullable)
{
booleanExpression = _hqlTreeBuilder.IsNull(lhs2);
}
else
{
booleanExpression = _hqlTreeBuilder.IsNull(rhs2);
}
return(_hqlTreeBuilder.BooleanOr(inequality, booleanExpression));
}