Database Redesign Which of the following SQL statements are helpful in database redesign? None of these Correlated subqueries only Both of the above are helpful EXISTS/NOT EXISTS expressions only None of these Correlated subqueries only Both of the above are helpful EXISTS/NOT EXISTS expressions only ANSWER DOWNLOAD EXAMIANS APP
Database Redesign Correlated subqueries are similar to a regular subquery. True False True False ANSWER DOWNLOAD EXAMIANS APP
Database Redesign Because of the need for extensive knowledge of SQL, many database developers choose to automate the redesign process. True False True False ANSWER DOWNLOAD EXAMIANS APP
Database Redesign Before any changes to database structure are attempted one should first: All of these test any changes on a test database only. create a complete backup of the operational database only. clearly understand the current structure and contents of the database only. All of these test any changes on a test database only. create a complete backup of the operational database only. clearly understand the current structure and contents of the database only. ANSWER DOWNLOAD EXAMIANS APP
Database Redesign Changing cardinalities in a database is: is impossible to do, so a new database must be constructed and the data moved into it. a common database design task. a rare database design task, but does occur. a database design task that never occurs. is impossible to do, so a new database must be constructed and the data moved into it. a common database design task. a rare database design task, but does occur. a database design task that never occurs. ANSWER DOWNLOAD EXAMIANS APP
Database Redesign The NOT EXISTS keyword will be true if: neither of these two conditions is met. all rows in the subquery fail the condition. both of these two conditions are met. any row in the subquery meets the condition. neither of these two conditions is met. all rows in the subquery fail the condition. both of these two conditions are met. any row in the subquery meets the condition. ANSWER DOWNLOAD EXAMIANS APP