private NPathSelectQuery ParseSelectQuery()
{
NPathSelectQuery query = new NPathSelectQuery();
queries.Push(query);
tokenizer.GetCurrentToken("select", "Select");
NPathSelectClause selectClause = new NPathSelectClause();
ParseSelectClause(selectClause);
query.Select = selectClause;
tokenizer.GetCurrentToken("from", "From");
NPathFromClause fromClause = new NPathFromClause();
ParseFromClause(fromClause);
query.From = fromClause;
if (tokenizer.GetCurrentToken().IsType("where"))
{
NPathWhereClause whereClause = new NPathWhereClause();
query.Where = whereClause;
ParseWhereClause(whereClause);
}
if (tokenizer.GetCurrentToken().IsType("order by")) // do not localize
{
NPathOrderByClause orderByClause = new NPathOrderByClause();
ParseOrderByClause(orderByClause);
query.OrderBy = orderByClause;
}
return(query);
}
private void ParseSelectClause(NPathSelectClause selectClause)
{
if (tokenizer.GetNextToken().IsType("distinct"))
{
selectClause.Distinct = true;
tokenizer.MoveNext();
}
if (tokenizer.GetNextToken().IsType("top"))
{
selectClause.HasTop = true;
tokenizer.MoveNext();
double top = double.Parse(tokenizer.GetNextToken("decimal", "Decimal value").Text); // do not localize
selectClause.Top = (int)top;
tokenizer.MoveNext();
if (tokenizer.GetNextToken().IsType("percent"))
{
selectClause.Percent = true;
tokenizer.MoveNext();
}
if (tokenizer.GetNextToken().IsType("with ties")) // do not localize
{
selectClause.WithTies = true;
tokenizer.MoveNext();
}
}
do
{
tokenizer.MoveNext();
{
IValue expression = ParseExpression();
NPathSelectField field = new NPathSelectField();
field.Expression = expression;
field.Alias = null;
selectClause.SelectFields.Add(field);
}
if (tokenizer.GetCurrentToken().IsType("as"))
{
NPathSelectField field = selectClause.SelectFields[selectClause.SelectFields.Count - 1] as NPathSelectField;
tokenizer.MoveNext();
field.Alias = tokenizer.GetCurrentToken().Text;
tokenizer.MoveNext();
}
} while (tokenizer.GetCurrentToken().IsType("comma"));
}
protected virtual void EmitSelect(NPathSelectQuery query)
{
NPathSelectClause select = query.Select;
Write("select "); // do not localize
if (query.Select.HasTop)
{
Write("top {0}", query.Select.Top); // do not localize
if (query.Select.Percent)
{
Write("% ");
}
}
int i = 0;
foreach (NPathSelectField field in select.SelectFields)
{
if (field.Expression is NPathIdentifier)
{
NPathIdentifier path = field.Expression as NPathIdentifier;
Write(path.Path);
}
if (field.Expression is NPathFunction)
{
NPathFunction function = field.Expression as NPathFunction;
EmitFunction(function);
}
if (field.Expression is NPathExpression)
{
NPathExpression expression = field.Expression as NPathExpression;
EmitExpression(expression);
}
if (field.Alias != null && field.Alias != "")
{
WriteLine(" as [{0}]", field.Alias); // do not localize
}
if (i < select.SelectFields.Count - 1)
{
Write(",");
}
i++;
}
WriteLine();
}
