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