Why SAP HANA has come with the concept of Projection?

[Former Member]

Hi All,

What's the main purpose of Projection in HANA and in what scenerio it is used? How different it is with Aggregation?

Thanks,

Pradeep

[Former Member]

Thank you very much Abani and Vivek. it helped me very much.

Regards,

Pradeep

[vivekbhoj]

Hi Pradeep,

You can also check the below thread:

Regards,

Vivek

[abanip]

Consider Projection as simple SELECT statement like

SELECT a, b FROM table_x where c = xx

where as Aggregation is like

SELECT a, SUM(d), MAX(e), COUNT(e) FROM table_x GROUP BY a

So a Projection node in HANA let you select a list of fields, you can also apply appropriate filters. An Aggregation node in HANA will let you compute the aggregate functions (SUM, MIN, MAX, AVG, COUNT etc).

Regards

Abani