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. test any changes on a test database only. create a complete backup of the operational database only. TRUE ANSWER : ? YOUR ANSWER : ?
What SQL command will allow you to change the table STUDENT to add the constraint named GradeCheck that states that the values of the Grade column must be greater than 0? ALTER TABLE STUDENT ALTER CONSTRAINT GradeCheck (Grade > 0); ALTER TABLE STUDENT ADD CONSTRAINT GradeCheck (Grade > 0); None of these ALTER TABLE STUDENT ADD CONSTRAINT GradeCheck CHECK (Grade > 0); TRUE ANSWER : ? YOUR ANSWER : ?
The data model produced from the reverse engineering process is a true logical model. True False TRUE ANSWER : ? YOUR ANSWER : ?
Which is not true of a correlated subquery? The processing of the SELECT statements is nested. EXISTS/NOT EXISTS is a form of a correlated subquery. They can be used to verify functional dependencies. They are very similar to a regular subquery. TRUE ANSWER : ? YOUR ANSWER : ?
Which SQL-92 standard SQL command can be used to change a table name? RENAME TABLE ALTER TABLE CHANGE TABLE None of these TRUE ANSWER : ? YOUR ANSWER : ?
Because of the importance of making data model changes correctly, many professionals are ________ about using an automated process for database redesign. optimistic None of these ambivalent skeptical TRUE ANSWER : ? YOUR ANSWER : ?
How many copies of the database schema are typically used in the redesign process? One Two Three Four TRUE ANSWER : ? YOUR ANSWER : ?
The NOT EXISTS keyword will be true if any row in the subquery meets the condition. False True TRUE ANSWER : ? YOUR ANSWER : ?
What SQL command can be used to add columns to a table? MODIFY TABLE TableName ADD COLUMN ColumnName MODIFY TABLE TableName ADD ColumnName ALTER TABLE TableName ADD COLUMN ColumnName ALTER TABLE TableName ADD ColumnName TRUE ANSWER : ? YOUR ANSWER : ?