1. In Oracle, when is it better to use materialized views?
A. It is always better to use materialized views because views are obsolete and materialized views replace them B. When a query is slow and its results need to be cached …show more content…
A primary key does not have to be unique; a unique key has to be unique B. A primary key is mandatory; a unique key is not mandatory C. Primary keys are not allowed on multiple columns, unique keys are allowed on multiple columns D. A primary key must start with PK; a unique key can start with any character E. No answer is correct
4. We have two tables, each with one column X of type number which is the primary key. Table A has 100 rows, Table B has 50 rows. When doing a Left Outer Join from A to B on X, which option would be correct?
A. The maximum number of rows is 100, the minimum number of rows 50 B. The maximum number of rows is 5000, the minimum number of rows 0 C. The maximum number of rows is 50, the minimum number of rows 0 D. The maximum number of rows is 100, the minimum number of rows 100 E. It is not possible to estimate a maximum and minimum. More information is …show more content…
A table “T” is given with a column “X” of type number. What does the following command do: "SELECT MAX(X) -1 FROM T"
A. It will return the second largest value X in T B. It will return the largest value of X, which is greater than minus one C. It will return a value that is greater by one than the maximum value of X in T D. It will return a value that is lesser by one than the maximum value of X in T E. It is an invalid query since MAX function must have a GROUP BY X in the end
6. What is Dual?
A. Dual is an internal Oracle database used for background backup and optimization B. Dual does not exist in Oracle, only in SQL Server C. Dual is an SQL command used to provide the dual value of a complex number D. Dual is an internal Oracle table that can be used for immediate queries E. No answer is correct
7. To concatenate two strings in Oracle, which of the following options can be used?
A. Use one single pipe character B. Use two single pipe characters C. Use one ampersand character D. Use two ampersand characters E. Use the CONCAT function
8. Complete the statement: A sequence in Oracle…
A. Will order a table automatically using some
A. It is always better to use materialized views because views are obsolete and materialized views replace them B. When a query is slow and its results need to be cached …show more content…
A primary key does not have to be unique; a unique key has to be unique B. A primary key is mandatory; a unique key is not mandatory C. Primary keys are not allowed on multiple columns, unique keys are allowed on multiple columns D. A primary key must start with PK; a unique key can start with any character E. No answer is correct
4. We have two tables, each with one column X of type number which is the primary key. Table A has 100 rows, Table B has 50 rows. When doing a Left Outer Join from A to B on X, which option would be correct?
A. The maximum number of rows is 100, the minimum number of rows 50 B. The maximum number of rows is 5000, the minimum number of rows 0 C. The maximum number of rows is 50, the minimum number of rows 0 D. The maximum number of rows is 100, the minimum number of rows 100 E. It is not possible to estimate a maximum and minimum. More information is …show more content…
A table “T” is given with a column “X” of type number. What does the following command do: "SELECT MAX(X) -1 FROM T"
A. It will return the second largest value X in T B. It will return the largest value of X, which is greater than minus one C. It will return a value that is greater by one than the maximum value of X in T D. It will return a value that is lesser by one than the maximum value of X in T E. It is an invalid query since MAX function must have a GROUP BY X in the end
6. What is Dual?
A. Dual is an internal Oracle database used for background backup and optimization B. Dual does not exist in Oracle, only in SQL Server C. Dual is an SQL command used to provide the dual value of a complex number D. Dual is an internal Oracle table that can be used for immediate queries E. No answer is correct
7. To concatenate two strings in Oracle, which of the following options can be used?
A. Use one single pipe character B. Use two single pipe characters C. Use one ampersand character D. Use two ampersand characters E. Use the CONCAT function
8. Complete the statement: A sequence in Oracle…
A. Will order a table automatically using some