public override IList <string> GetColumns()
{
var safeGetColumns = new Func <string, IList <string> >(nodeId =>
{
if (InputDict.ContainsKey(nodeId))
{
return(InputDict[nodeId].GetColumns());
}
else
{
return(new List <string>());
}
});
var columnLists = Inputs.Select(i => safeGetColumns(i));
if (columnLists.Any())
{
if (IncludeUniqueColumns)
{
// build a full column list from all inputs
return(columnLists.Aggregate((x, y) => new List <string>(new HashSet <string>(x).Union(y))));
}
else
{
// build an intersection of the column lists from all inputs
return(columnLists.Aggregate((x, y) => new List <string>(new HashSet <string>(x).Intersect(y))));
}
}
else
{
return(new List <string>());
}
}
public override IList <string> GetColumnTypes()
{
if (Inputs.All(i => InputDict.ContainsKey(i)))
{
var input1 = InputDict[Inputs[0]];
var input2 = InputDict[Inputs[1]];
var result = new List <string>();
result.AddRange(input1.GetColumnTypes().Select(c => c));
result.AddRange(input2.GetColumnTypes().Select(c => c));
return(result);
}
else
{
return(new List <string>());
}
}