DATABASE REDESIGN QUIZ

Neither of the above actions will succeed

Changing a column data type from char to date

Both of the above actions should succeed

Changing a column data type from numeric to char

False

True

EXISTS/NOT EXISTS expressions only

None of these

Correlated subqueries only

Both of the above are helpful

True

False

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.

ALTER TABLE TableName DROP ColumnName

MODIFY TABLE TableName DROP ColumnName

ALTER TABLE TableName DROP COLUMN ColumnName

MODIFY TABLE TableName DROP COLUMN ColumnName

True

False

True

False

False

True

None of these

an internal model.

a conceptual model.

a logical model.