Tag: databases

You can join a maximum of two tables through an equijoin

You can join a maximum of two columns through an equijoin

You specify an equijoin condition in the SELECT or FROM clauses of a SELECT statement

To join two tables through an equijoin, the columns in the join condition must be primary key and foreign key columns.

You can join n tables (all having single column primary keys) in a SQL statement by specifying a minimum of n-1 join conditions.

WHERE

HAVING

RESTRICT

GROUP BY

ORDER BY

Create groups of data

Sort data in a specific order

Convert data to a different format

Retrieve data based on an unknown condition

query will retrieve only one row

authorization failure

no such code available

rollback

TSO

IMC

CICS

None of the above

returns 5 rows

returns 3 rows

returns all 8rows

none

You cannot use IN operator in a condition that involves an outerjoin

You use (+) on both sides of the WHERE condition to perform an outerjoin

You use (*) on both sides of the WHERE condition to perform an outerjoin

You use an outerjoin to see only the rows that do not meet the join condition

In the WHERE condition, you use (+) following the name of the column in the table

You cannot link a condition that is involved in an outerjoin to another condition by

DELETE employees;

DESCRIBE employees;

ROLLBACK TO SAVEPOINT C;

GRANT SELECT ON employees TO SCOTT;

ALTER TABLE employees SET UNUSED COLUMN sal;

Select MAX(sal) FROM employees WHERE department_id = 20;

You can use aggregate functions in any clause of a SELECT statement.

You can use aggregate functions only in the column list of the SELECT clause and in the WHERE clause of a SELECT statement.

You can mix single row columns with aggregate functions in the column list of a SELECT statement by grouping on the single row columns.

You can pass column names, expressions, constants, or functions as parameters to an aggregate function.

You can use aggregate functions on a table, only by grouping the whole table as one single group.

You cannot group the rows of a table by more than one column while using aggregate functions.

COUNT

SUM

COMPUTE

MIN