EXPLAIN PLAN for query of sales and products tables
EXPLAIN PLAN FOR
SELECT prod_category, AVG(amount_sold)
FROM sh.sales s, sh.products p
WHERE p.prod_id = s.prod_id
GROUP BY prod_category
Statement processed.
Use DBMS_XPLAN to display the execution plan
SELECT plan_table_output
FROM TABLE(DBMS_XPLAN.DISPLAY('plan_table',null,'typical'))
PLAN_TABLE_OUTPUT |
---|
Plan hash value: 1197568639 |
------------------------------------------------------------------------------------------------------------------------- |
| Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time | Pstart| Pstop | |
------------------------------------------------------------------------------------------------------------------------- |
| 0 | SELECT STATEMENT | | 5 | 255 | 654 (8)| 00:00:01 | | | |
| 1 | HASH GROUP BY | | 5 | 255 | 654 (8)| 00:00:01 | | | |
|* 2 | HASH JOIN | | 72 | 3672 | 653 (8)| 00:00:01 | | | |
| 3 | VIEW | VW_GBC_5 | 72 | 2160 | 651 (8)| 00:00:01 | | | |
| 4 | HASH GROUP BY | | 72 | 648 | 651 (8)| 00:00:01 | | | |
| 5 | PARTITION RANGE ALL | | 918K| 8075K| 613 (2)| 00:00:01 | 1 | 28 | |
| 6 | TABLE ACCESS STORAGE FULL | SALES | 918K| 8075K| 613 (2)| 00:00:01 | 1 | 28 | |
| 7 | VIEW | index$_join$_002 | 72 | 1512 | 2 (0)| 00:00:01 | | | |
|* 8 | HASH JOIN | | | | | | | | |
| 9 | INDEX STORAGE FAST FULL SCAN| PRODUCTS_PK | 72 | 1512 | 1 (0)| 00:00:01 | | | |
| 10 | INDEX STORAGE FAST FULL SCAN| PRODUCTS_PROD_CAT_IX | 72 | 1512 | 1 (0)| 00:00:01 | | | |
------------------------------------------------------------------------------------------------------------------------- |
Predicate Information (identified by operation id): |
--------------------------------------------------- |
2 - access("P"."PROD_ID"="ITEM_1") |
8 - access(ROWID=ROWID) |