/// <summary>nothing has been pre-consumed</summary>
/// <returns>null if there is no order by</returns>
/// <exception cref="System.SqlSyntaxErrorException" />
protected internal virtual GroupBy GroupBy()
{
if (lexer.Token() != MySqlToken.KwGroup)
{
return(null);
}
lexer.NextToken();
Match(MySqlToken.KwBy);
var expr = exprParser.Expression();
var order = SortOrder.Asc;
GroupBy groupBy;
switch (lexer.Token())
{
case MySqlToken.KwDesc:
{
order = SortOrder.Desc;
goto case MySqlToken.KwAsc;
}
case MySqlToken.KwAsc:
{
lexer.NextToken();
goto default;
}
default:
{
break;
}
}
switch (lexer.Token())
{
case MySqlToken.KwWith:
{
lexer.NextToken();
MatchIdentifier("ROLLUP");
return(new GroupBy(expr, order, true));
}
case MySqlToken.PuncComma:
{
break;
}
default:
{
return(new GroupBy(expr, order, false));
}
}
for (groupBy = new GroupBy().AddOrderByItem(expr, order);
lexer.Token() == MySqlToken.PuncComma;)
{
lexer.NextToken();
order = SortOrder.Asc;
expr = exprParser.Expression();
switch (lexer.Token())
{
case MySqlToken.KwDesc:
{
order = SortOrder.Desc;
goto case MySqlToken.KwAsc;
}
case MySqlToken.KwAsc:
{
lexer.NextToken();
goto default;
}
default:
{
break;
}
}
groupBy.AddOrderByItem(expr, order);
if (lexer.Token() == MySqlToken.KwWith)
{
lexer.NextToken();
MatchIdentifier("ROLLUP");
return(groupBy.SetWithRollup());
}
}
return(groupBy);
}