Databases Reference
In-Depth Information
3.
Execute the following queries to verify the execution plan adopted by the database:
SET AUTOT TRACE EXP STAT
SELECT COUNT(*) FROM MYCUSTOMERS
WHERE CUST_GENDER = ‹F›;
SELECT COUNT(*) FROM MYCUSTOMERS
WHERE CUST_MARITAL_STATUS = ‹single›;
SELECT COUNT(*) FROM MYCUSTOMERS
WHERE CUST_MARITAL_STATUS = ‹married› AND CUST_GENDER = ‹F›;
SELECT COUNT(*) FROM MYCUSTOMERS
WHERE CUST_MARITAL_STATUS = ‹single› AND CUST_GENDER = ‹M›
AND CUST_YEAR_OF_BIRTH BETWEEN 1970 AND 1980;
SELECT COUNT(*) FROM MYCUSTOMERS
WHERE CUST_MARITAL_STATUS = ‹single›
AND CUST_YEAR_OF_BIRTH BETWEEN 1970 AND 1980;
SELECT COUNT(*) FROM MYCUSTOMERS
WHERE CUST_YEAR_OF_BIRTH BETWEEN 1970 AND 1980;
4. In the next screenshot, we can see the results for the first query executed:
