public override ISqlFragment Visit(NewInstancePredicate e)
{
Check.NotNull(e, "e");
if (BuiltInTypeKind.CollectionType == e.ResultType.EdmType.BuiltInTypeKind)
{
return(VisitCollectionConstructor(e));
}
throw new NotSupportedException();
}
private ISqlFragment VisitNewInstanceExpression(NewInstancePredicate e, bool aliasesNeedRenaming, out Dictionary <string, Symbol> newColumns)
{
var result = new SqlBuilder();
var rowType = e.ResultType.EdmType as RowType;
if (null != rowType)
{
newColumns = new Dictionary <string, Symbol>(e.Arguments.Count);
var members = rowType.Properties;
var separator = "";
for (var i = 0; i < e.Arguments.Count; ++i)
{
var argument = e.Arguments[i];
if (BuiltInTypeKind.RowType == argument.ResultType.EdmType.BuiltInTypeKind)
{
throw new NotSupportedException();
}
var member = members[i];
result.Append(separator);
result.AppendLine();
result.Append(argument.Accept(this));
result.Append(" AS ");
if (aliasesNeedRenaming)
{
var column = new Symbol(member.Name, member.TypeUsage);
column.NeedsRenaming = true;
column.NewName = String.Concat("Internal_", member.Name);
result.Append(column);
newColumns.Add(member.Name, column);
}
else
{
result.Append(QuoteIdentifier(member.Name));
}
separator = ", ";
}
}
else
{
throw new NotSupportedException();
}
return(result);
}
private ISqlFragment VisitCollectionConstructor(NewInstancePredicate e)
{
if (e.Arguments.Count == 1 && e.Arguments[0].PredicateType == PredicateType.Element)
{
var elementExpr = e.Arguments[0] as ElementPredicate;
var result = VisitExpressionEnsureSqlStatement(elementExpr.Argument);
if (!IsCompatible(result, PredicateType.Element))
{
Symbol fromSymbol;
var inputType = elementExpr.Argument.ResultType.GetElementTypeUsage();
result = CreateNewSelectStatement(result, "element", inputType, out fromSymbol);
AddFromSymbol(result, "element", fromSymbol, false);
}
result.Select.Top = new TopClause(1, false);
return(result);
}
var collectionType = (CollectionType)e.ResultType.EdmType;
var isScalarElement = BuiltInTypeKind.PrimitiveType == collectionType.TypeUsage.EdmType.BuiltInTypeKind;
var resultSql = new SqlBuilder();
var separator = "";
if (e.Arguments.Count == 0)
{
//resultSql.Append(" SELECT CAST(null as ");
//resultSql.Append(GetSqlPrimitiveType(collectionType.TypeUsage));
//resultSql.Append(") AS X FROM (SELECT 1) AS Y WHERE 1=0");
}
foreach (var arg in e.Arguments)
{
resultSql.Append(separator);
resultSql.Append(" SELECT ");
resultSql.Append(arg.Accept(this));
if (isScalarElement)
{
resultSql.Append(" AS X ");
}
separator = " UNION ALL ";
}
return(resultSql);
}
