Skip Headers
Oracle® Database SQL Language Reference
11g Release 2 (11.2)

E41084-02
Go to Documentation Home
Home
Go to Book List
Book List
Go to Table of Contents
Contents
Go to Index
Index
Go to Master Index
Master Index
Go to Feedback page
Contact Us

Go to previous page
Previous
Go to next page
Next
PDF · Mobi · ePub

GROUPING_ID

Syntax

Description of grouping_id.gif follows
Description of the illustration grouping_id.gif

Purpose

GROUPING_ID returns a number corresponding to the GROUPING bit vector associated with a row. GROUPING_ID is applicable only in a SELECT statement that contains a GROUP BY extension, such as ROLLUP or CUBE, and a GROUPING function. In queries with many GROUP BY expressions, determining the GROUP BY level of a particular row requires many GROUPING functions, which leads to cumbersome SQL. GROUPING_ID is useful in these cases.

GROUPING_ID is functionally equivalent to taking the results of multiple GROUPING functions and concatenating them into a bit vector (a string of ones and zeros). By using GROUPING_ID you can avoid the need for multiple GROUPING functions and make row filtering conditions easier to express. Row filtering is easier with GROUPING_ID because the desired rows can be identified with a single condition of GROUPING_ID = n. The function is especially useful when storing multiple levels of aggregation in a single table.

Examples

The following example shows how to extract grouping IDs from a query of the sample table sh.sales:

SELECT channel_id, promo_id, sum(amount_sold) s_sales,
       GROUPING(channel_id) gc,
       GROUPING(promo_id) gp,
       GROUPING_ID(channel_id, promo_id) gcp,
       GROUPING_ID(promo_id, channel_id) gpc
  FROM sales
  WHERE promo_id > 496
  GROUP BY CUBE(channel_id, promo_id)
  ORDER BY channel_id, promo_id, s_sales, gc;
 
CHANNEL_ID   PROMO_ID    S_SALES         GC         GP        GCP        GPC
---------- ---------- ---------- ---------- ---------- ---------- ----------
         2        999 25797563.2          0          0          0          0
         2            25797563.2          0          1          1          2
         3        999 55336945.1          0          0          0          0
         3            55336945.1          0          1          1          2
         4        999 13370012.5          0          0          0          0
         4            13370012.5          0          1          1          2
                  999 94504520.8          1          0          2          1
                      94504520.8          1          1          3          3