public Task <IPhysicalOperator <RowHolder> > BuildStatement(Sql.sqlStatement statement, ITransaction tran, IPhysicalOperator <RowHolder> source, InputStringNormalizer inputStringNormalizer)
{
Sql.columnSelect[] columns = new Sql.columnSelect[0];
Tuple <Sql.aggType, string>[] aggregates = new Tuple <Sql.aggType, string> [0];
if (!statement.Columns.IsStar)
{
columns = (((Sql.selectType.ColumnList)statement.Columns).Item).ToArray();
aggregates = columns
.Where(c => c.IsAggregate == true)
.Select(c => ((Sql.columnSelect.Aggregate)c).Item).ToArray();
}
if (statement.GroupBy.Any() || aggregates.Any())
{
string[] groupByColumns = statement.GroupBy.ToArray();
GroupByFunctors groupByFunctors = GroupByStatementBuilder.EvalGroupBy(groupByColumns, columns, source.GetOutputColumns());
IPhysicalOperator <RowHolder> phyOpGroupBy = new PhyOpGroupBy(source, groupByFunctors);
return(Task.FromResult(phyOpGroupBy));
}
else
{
return(Task.FromResult(source));
}
}
public Task <IPhysicalOperator <RowHolder> > BuildStatement(Sql.sqlStatement statement, ITransaction tran, IPhysicalOperator <RowHolder> source, InputStringNormalizer inputStringNormalizer)
{
Sql.columnSelect[] columns = new Sql.columnSelect[0];
bool isStar = false;
string[] projections = new string[0];
if (statement.GroupBy.Any())
{
// no job for me, this is group by.
return(Task.FromResult(source));
}
if (!statement.Columns.IsStar)
{
columns = (((Sql.selectType.ColumnList)statement.Columns).Item).ToArray();
if (columns.Any(c => c.IsAggregate == true))
{
// No job for me, this is aggregation.
return(Task.FromResult(source));
}
projections = columns
.Where(c => c.IsProjection == true)
.Select(c => ((Sql.columnSelect.Projection)c).Item).ToArray();
}
else
{
isStar = true;
}
int?topRows = null;
if (FSharpOption <int> .get_IsSome(statement.Top))
{
topRows = statement.Top.Value;
if (topRows < 1)
{
throw new InvalidTopCountException();
}
}
if (isStar)
{
// no need for project, just return everything.
IPhysicalOperator <RowHolder> projectOp = new PhyOpProject(source, topRows);
return(Task.FromResult(projectOp));
}
else
{
// Project Op.
List <MetadataColumn> columnMapping = new List <MetadataColumn>();
foreach (string columnName in projections)
{
MetadataColumn mc = QueryProcessingAccessors.GetMetadataColumn(columnName, source.GetOutputColumns());
columnMapping.Add(mc);
}
IPhysicalOperator <RowHolder> projectOp = new PhyOpProject(source, columnMapping.Select(mc => mc.ColumnId).ToArray(), topRows);
return(Task.FromResult(projectOp));
}
}
