Database Redesign Before any changes to database structure are attempted one should first: All of these clearly understand the current structure and contents of the database only. create a complete backup of the operational database only. test any changes on a test database only. All of these clearly understand the current structure and contents of the database only. create a complete backup of the operational database only. test any changes on a test database only. ANSWER DOWNLOAD EXAMIANS APP
Database Redesign Which of the following modifications may not succeed? Changing a column data type from numeric to char Both of the above actions should succeed Changing a column data type from char to date Neither of the above actions will succeed Changing a column data type from numeric to char Both of the above actions should succeed Changing a column data type from char to date Neither of the above actions will succeed ANSWER DOWNLOAD EXAMIANS APP
Database Redesign How can you find rows that do not match some specified condition? None of these EXISTS NOT EXISTS Double use of NOT EXISTS None of these EXISTS NOT EXISTS Double use of NOT EXISTS ANSWER DOWNLOAD EXAMIANS APP
Database Redesign A regular subquery can be processed: None of these from the top down. from the bottom up. by nesting. None of these from the top down. from the bottom up. by nesting. ANSWER DOWNLOAD EXAMIANS APP
Database Redesign What SQL command can be used to add columns to a table? ALTER TABLE TableName ADD COLUMN ColumnName MODIFY TABLE TableName ADD ColumnName ALTER TABLE TableName ADD ColumnName MODIFY TABLE TableName ADD COLUMN ColumnName ALTER TABLE TableName ADD COLUMN ColumnName MODIFY TABLE TableName ADD ColumnName ALTER TABLE TableName ADD ColumnName MODIFY TABLE TableName ADD COLUMN ColumnName ANSWER DOWNLOAD EXAMIANS APP