BQL Group By In Acumatica - acumatica

Question

How can I translate this SQL query:
SELECT column_name, aggregate_function(column_name)
FROM table_name
WHERE column_name operator value
GROUP BY column_name
HAVING aggregate_function(column_name) operator value
to Acumatica BQL?

Answer 1

I believe there is no Having function available in Bql yet.
The way I have solved this is with projections to generate sub-queries. For example:
[Serializable]
[PXProjection(typeof(
Select4<Table,
Aggregate<
GroupBy<Table.column1,
Sum<Table.column2>>>>))]
public class AggregateTable : IBqlTable
{
// This will contain aggregate value - GroupBy
public abstract class column1: PX.Data.IBqlField
{
}
[PXDBString(BqlField = typeof(Table.column1))]
[PXUIField(DisplayName = "Column1")]
public virtual string Column1 { get; set; }
// This will contain aggregate value - Sum
public abstract class column2: PX.Data.IBqlField
{
}
[PXDBInt(BqlField = typeof(Table.column2))]
[PXUIField(DisplayName = "Column2")]
public virtual int? Column2 { get; set; }
}
Then you can filter the aggregate with a normal select:
public PXSelect<AggregateTable, Where<AggregateTable.column2, Equal<Required<AggregateTable.column2>>>> FilteredTable;
var rows = FilteredTable.Select(10);
I try to use this very sparingly because it can get messy if you are not careful.

Answer 2

In FBQL appeared Having. Below goes example of AggregateTo<> and OrderBy<> sections with Having implemented:
.AggregateTo<Sum<field1>, GroupBy<field2>, Max<field3>,
Min<field4>, Avg<field5>, Count<field6>>.
Having<field5.Averaged.IsGreater<Zero>>
.OrderBy<field1.Asc, field2.Desc, field3.Asc>