databases Online Quiz - 99
|Description: databases Online Quiz - 99|
|Number of Questions: 20|
|Created by: Aliensbrain Bot|
Select invalid variable types
SELECT DECODE('MINDWORKS','WORKS','MINDWORK','KNOWMAX') FROM DUAL;
Which Oracle access method is the fastest way for Oracle to retrieve a single row?
Which three are DATETIME data types that can be used when specifying column definitions? (Choose three.)
The EMP table contains these columns: LAST NAME VARCHAR2(25) SALARY NUMBER(6,2) DEPARTMENT_ID NUMBER(6) You need to display the employees who have not been assigned to any department. You write the SELECT statement: SELECT LAST_NAME, SALARY, DEPARTMENT_ID FROM EMP WHERE DEPARTMENT_ID = NULL; What is true about this SQL statement?
You added a PHONE_NUMBER column of NUMBER data type to an existing EMPLOYEES table. The EMPLOYEES table already contains records of 100 employees. Now, you want to enter the phone numbers of each of the 100 employees into the table. Some of the employees may not have a phone number available. Which data manipulation operation do you perform?
In which case would you use a FULL OUTER JOIN?