CHAPTER 2
Which of the following keywords can be used to change the size, datatype, and/or default value of an existing column?
MODIFY
DDL commands are used to create or modify database objects.
TRUE
More than one column can be changed at a time with the ALTER TABLE...MODIFY command.
TRUE
When adding a column to an existing table, the ____________________ clause must be used with the ALTER TABLE command.
ADD
The ____ TABLE command is used to modify an existing column's data declaration.
ALTER
Data manipulation language commands are used to create or modify database tables.
FALSE
Only one column can be added to an existing table at one time.
FALSE
The ALTER TABLE name can be used to rename a table.
FALSE
The CHANGE TABLE command can be used to modify an existing table.
FALSE
The data contained in a dropped table can be retrieved if the DROP option was not used in the DROP TABLE command.
FALSE
To retain the structure of a table, while deleting all its data and releasing their storage space, execute the TRUNC command.
FALSE
The DROP COLUMN clause of the ALTER TABLE command can be used to drop a maximum of ____________________ column(s) at a time.
ONE
The DROP COLUMN clause of the ALTER TABLE command can only be used to delete one column at a time.
TRUE
The DROP TABLE command can be used to remove a table and all its data from a database.
TRUE
Deleting columns from a table is a(n) ____ action.
UNRESTRICTED
Which of the following column data type changes is permitted?
VARCHAR2 to CHAR
Adding a new column to a database table is a(n) ____________________ action.
UNRESTRICTED
The ____________________ command can be used to modify the structure of a table.
ALTER TABLE
The DELETE TABLE command can be used to delete all the data stored in a table and release the storage space, yet retain the structure of the table.
FALSE
The MODIFY TABLE command can be used to change the size of a table.
FALSE
The MODIFY clause can be used with the ALTER TABLE command to add a column to an existing table.
FALSE
The SQL command to create a database table is an example of DML.
FALSE
The TRUNCATE TABLE command can be used to delete a table from a database.
FALSE
When a column is deleted, the deletion is permanent.
TRUE
You cannot delete the last column in a table.
TRUE
To delete all the rows in a table and free up the storage space that was occupied by those rows, the ____ command should be used.
TRUNCATE TABLE
When using the ALTER TABLE...DROP COLUMN command, which of the following is not correct?
The command can be used to delete multiple columns from a table.