private static void SetSqlTypeIfSimpleExpression(SqlExpression expression, ProviderType sqlType)
{
SqlSimpleTypeExpression simpleExpression = expression as SqlSimpleTypeExpression;
if (simpleExpression != null)
{
simpleExpression.SetSqlType(sqlType);
}
}
internal override SqlExpression VisitLike(SqlLike like)
{
base.VisitLike(like);
// When comparing a unicode pattern against a non-unicode expression,
// we want retype the pattern as non-unicode.
if (!like.Expression.SqlType.IsUnicodeType && like.Pattern.SqlType.IsUnicodeType &&
(like.Pattern.NodeType == SqlNodeType.Value || like.Pattern.NodeType == SqlNodeType.ClientParameter))
{
SqlSimpleTypeExpression pattern = (SqlSimpleTypeExpression)like.Pattern;
pattern.SetSqlType(pattern.SqlType.GetNonUnicodeEquivalent());
}
return(like);
}
internal override SqlExpression VisitBinaryOperator(SqlBinary bo)
{
base.VisitBinaryOperator(bo);
if (bo.NodeType.IsComparisonOperator() &&
bo.Left.ClrType != typeof(bool) && bo.Right.ClrType != typeof(bool))
{
// Strip unnecessary CONVERT calls.
if (bo.Left.NodeType == SqlNodeType.Convert)
{
var conv = (SqlUnary)bo.Left;
if (CanDbConvert(conv.Operand.ClrType, bo.Right.ClrType) &&
conv.Operand.SqlType.ComparePrecedenceTo(bo.Right.SqlType) != 1)
{
return(VisitBinaryOperator(new SqlBinary(bo.NodeType, bo.ClrType, bo.SqlType, conv.Operand, bo.Right)));
}
}
if (bo.Right.NodeType == SqlNodeType.Convert)
{
var conv = (SqlUnary)bo.Right;
if (CanDbConvert(conv.Operand.ClrType, bo.Left.ClrType) &&
conv.Operand.SqlType.ComparePrecedenceTo(bo.Left.SqlType) != 1)
{
return(VisitBinaryOperator(new SqlBinary(bo.NodeType, bo.ClrType, bo.SqlType, bo.Left, conv.Operand)));
}
}
}
if (bo.Right != null && bo.NodeType != SqlNodeType.Concat)
{
SqlExpression left = bo.Left;
SqlExpression right = bo.Right;
this.CoerceBinaryArgs(ref left, ref right);
if (bo.Left != left || bo.Right != right)
{
bo = sql.Binary(bo.NodeType, left, right);
}
bo.SetSqlType(typeProvider.PredictTypeForBinary(bo.NodeType, left.SqlType, right.SqlType));
}
if (bo.NodeType.IsComparisonOperator())
{
// When comparing a unicode value against a non-unicode column,
// we want retype the parameter as non-unicode.
Func <SqlExpression, SqlExpression, bool> needsRetype =
(expr, val) => (val.NodeType == SqlNodeType.Value || val.NodeType == SqlNodeType.ClientParameter) &&
!(expr.NodeType == SqlNodeType.Value || expr.NodeType == SqlNodeType.ClientParameter) &&
val.SqlType.IsUnicodeType && !expr.SqlType.IsUnicodeType;
SqlSimpleTypeExpression valueToRetype = null;
if (needsRetype(bo.Left, bo.Right))
{
valueToRetype = (SqlSimpleTypeExpression)bo.Right;
}
else if (needsRetype(bo.Right, bo.Left))
{
valueToRetype = (SqlSimpleTypeExpression)bo.Left;
}
if (valueToRetype != null)
{
valueToRetype.SetSqlType(valueToRetype.SqlType.GetNonUnicodeEquivalent());
}
}
return(bo);
}