internal virtual SqlExpression VisitDiscriminatorOf(SqlDiscriminatorOf dof) {
dof.Object = this.VisitExpression(dof.Object);
return dof;
}
internal override SqlExpression VisitDiscriminatorOf(SqlDiscriminatorOf dof)
{
if(_isDebugMode)
{
_commandStringBuilder.Append("DISCO(");
}
base.VisitDiscriminatorOf(dof);
if(_isDebugMode)
{
_commandStringBuilder.Append(")");
}
return dof;
}
/// <summary>
/// Evaluate the object and extract its discriminator.
/// </summary>
internal override SqlExpression VisitDiscriminatorOf(SqlDiscriminatorOf dof) {
SqlExpression obj = this.FetchExpression(dof.Object); // FetchExpression removes Link.
// It's valid to unwrap optional and outer-join values here because type case already handles
// NULL values correctly.
while (obj.NodeType == SqlNodeType.OptionalValue
|| obj.NodeType == SqlNodeType.OuterJoinedValue) {
if (obj.NodeType == SqlNodeType.OptionalValue) {
obj = ((SqlOptionalValue)obj).Value;
}
else {
obj = ((SqlUnary)obj).Operand;
}
}
if (obj.NodeType == SqlNodeType.TypeCase) {
SqlTypeCase tc = (SqlTypeCase)obj;
// Rewrite a case of discriminators. We can't just reduce to
// discriminator (yet) because the ELSE clause needs to be considered.
// Later in the conversion there is an optimization that will turn the CASE
// into a simple combination of ANDs and ORs.
// Also, cannot reduce to IsNull(Discriminator,DefaultDiscriminator) because
// other unexpected values besides NULL need to be handled.
List<SqlExpression> matches = new List<SqlExpression>();
List<SqlExpression> values = new List<SqlExpression>();
MetaType defaultType = tc.RowType.InheritanceDefault;
object discriminator = defaultType.InheritanceCode;
foreach (SqlTypeCaseWhen when in tc.Whens) {
matches.Add(when.Match);
if (when.Match == null) {
SqlExpression @default = sql.Value(discriminator.GetType(), tc.Whens[0].Match.SqlType, defaultType.InheritanceCode, true, tc.SourceExpression);
values.Add(@default);
}
else {
// Must duplicate so that columnizer doesn't nominate the match as a value.
values.Add(sql.Value(discriminator.GetType(), when.Match.SqlType, ((SqlValue)when.Match).Value, true, tc.SourceExpression));
}
}
return sql.Case(tc.Discriminator.ClrType, tc.Discriminator, matches, values, tc.SourceExpression);
} else {
var mt = this.model.GetMetaType(obj.ClrType).InheritanceRoot;
if (mt.HasInheritance) {
return this.VisitExpression(sql.Member(dof.Object, mt.Discriminator.Member));
}
}
return sql.TypedLiteralNull(dof.ClrType, dof.SourceExpression);
}
internal override SqlExpression VisitDiscriminatorOf(SqlDiscriminatorOf dof)
{
return new SqlDiscriminatorOf(this.VisitExpression(dof.Object), dof.ClrType, dof.SqlType, dof.SourceExpression);
}
internal override SqlExpression VisitMethodCall(SqlMethodCall mc)
{
mc.Object = this.VisitExpression(mc.Object);
for(int i = 0, n = mc.Arguments.Count; i < n; i++)
{
mc.Arguments[i] = this.VisitExpression(mc.Arguments[i]);
}
if(mc.Method.IsStatic)
{
if(mc.Method.Name == "Equals" && mc.Arguments.Count == 2)
{
return sql.Binary(SqlNodeType.EQ2V, mc.Arguments[0], mc.Arguments[1], mc.Method);
}
if(mc.Method.DeclaringType == typeof(string) && mc.Method.Name == "Concat")
{
SqlClientArray arr = mc.Arguments[0] as SqlClientArray;
List<SqlExpression> exprs = null;
if(arr != null)
{
exprs = arr.Expressions;
}
else
{
exprs = mc.Arguments;
}
if(exprs.Count == 0)
{
return sql.ValueFromObject("", false, mc.SourceExpression);
}
SqlExpression sum;
if(exprs[0].SqlType.IsString || exprs[0].SqlType.IsChar)
{
sum = exprs[0];
}
else
{
sum = sql.ConvertTo(typeof(string), exprs[0]);
}
for(int i = 1; i < exprs.Count; i++)
{
if(exprs[i].SqlType.IsString || exprs[i].SqlType.IsChar)
{
sum = sql.Concat(sum, exprs[i]);
}
else
{
sum = sql.Concat(sum, sql.ConvertTo(typeof(string), exprs[i]));
}
}
return sum;
}
if(IsVbIIF(mc))
{
return TranslateVbIIF(mc);
}
switch(mc.Method.Name)
{
case "op_Equality":
return sql.Binary(SqlNodeType.EQ, mc.Arguments[0], mc.Arguments[1], mc.Method, mc.ClrType);
case "op_Inequality":
return sql.Binary(SqlNodeType.NE, mc.Arguments[0], mc.Arguments[1], mc.Method, mc.ClrType);
case "op_LessThan":
return sql.Binary(SqlNodeType.LT, mc.Arguments[0], mc.Arguments[1], mc.Method, mc.ClrType);
case "op_LessThanOrEqual":
return sql.Binary(SqlNodeType.LE, mc.Arguments[0], mc.Arguments[1], mc.Method, mc.ClrType);
case "op_GreaterThan":
return sql.Binary(SqlNodeType.GT, mc.Arguments[0], mc.Arguments[1], mc.Method, mc.ClrType);
case "op_GreaterThanOrEqual":
return sql.Binary(SqlNodeType.GE, mc.Arguments[0], mc.Arguments[1], mc.Method, mc.ClrType);
case "op_Multiply":
return sql.Binary(SqlNodeType.Mul, mc.Arguments[0], mc.Arguments[1], mc.Method, mc.ClrType);
case "op_Division":
return sql.Binary(SqlNodeType.Div, mc.Arguments[0], mc.Arguments[1], mc.Method, mc.ClrType);
case "op_Subtraction":
return sql.Binary(SqlNodeType.Sub, mc.Arguments[0], mc.Arguments[1], mc.Method, mc.ClrType);
case "op_Addition":
return sql.Binary(SqlNodeType.Add, mc.Arguments[0], mc.Arguments[1], mc.Method, mc.ClrType);
case "op_Modulus":
return sql.Binary(SqlNodeType.Mod, mc.Arguments[0], mc.Arguments[1], mc.Method, mc.ClrType);
case "op_BitwiseAnd":
return sql.Binary(SqlNodeType.BitAnd, mc.Arguments[0], mc.Arguments[1], mc.Method, mc.ClrType);
case "op_BitwiseOr":
return sql.Binary(SqlNodeType.BitOr, mc.Arguments[0], mc.Arguments[1], mc.Method, mc.ClrType);
case "op_ExclusiveOr":
return sql.Binary(SqlNodeType.BitXor, mc.Arguments[0], mc.Arguments[1], mc.Method, mc.ClrType);
case "op_UnaryNegation":
return sql.Unary(SqlNodeType.Negate, mc.Arguments[0], mc.Method, mc.SourceExpression);
case "op_OnesComplement":
return sql.Unary(SqlNodeType.BitNot, mc.Arguments[0], mc.Method, mc.SourceExpression);
case "op_False":
return sql.Unary(SqlNodeType.Not, mc.Arguments[0], mc.Method, mc.SourceExpression);
}
}
else
{
if(mc.Method.Name == "Equals" && mc.Arguments.Count == 1)
{
return sql.Binary(SqlNodeType.EQ, mc.Object, mc.Arguments[0]);
}
if(mc.Method.Name == "GetType" && mc.Arguments.Count == 0)
{
MetaType mt = TypeSource.GetSourceMetaType(mc.Object, this.model);
if(mt.HasInheritance)
{
Type discriminatorType = mt.Discriminator.Type;
SqlDiscriminatorOf discriminatorOf = new SqlDiscriminatorOf(mc.Object, discriminatorType, this.sql.TypeProvider.From(discriminatorType), mc.SourceExpression);
return this.VisitExpression(sql.DiscriminatedType(discriminatorOf, mt));
}
return this.VisitExpression(sql.StaticType(mt, mc.SourceExpression));
}
}
return mc;
}