public static QsiColumnsDeclarationNode VisitSelectElements(SelectElementsContext context)
{
return(TreeHelper.Create <QsiColumnsDeclarationNode>(n =>
{
if (context.star != null)
{
n.Columns.Add(new QsiAllColumnNode());
}
n.Columns.AddRange(context.selectElement().Select(VisitSelectElement));
}));
}
public static IColumn[] VisitSelectElements(SelectElementsContext context)
{
if (context.star != null)
{
return(new IColumn[]
{
new StarColumn()
});
}
IColumn[] columns = context.selectElement().Select(VisitSelectElement).ToArray();
if (columns.Any(c => c is CountFunctionColumn) && columns.Length > 1)
{
throw new InvalidOperationException("Count function can only use in single column.");
}
return(columns);
}