Rename operation in DBMS Theory - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to rename a table from old_table to new_table.

DBMS Theory

ALTER TABLE old_table [1] new_table;

Drag options to blanks, or click blank then click option'

ARENAME TO

BUPDATE TO

CMODIFY TO

DCHANGE TO

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'CHANGE TO' or 'MODIFY TO' instead of 'RENAME TO'.

Forgetting the 'TO' keyword after 'RENAME'.

In SQL, the correct syntax to rename a table is ALTER TABLE old_table RENAME TO new_table;. The keyword RENAME TO is used for this operation.

2fill in blank

medium

Complete the code to rename a column old_column to new_column in the table my_table.

DBMS Theory

ALTER TABLE my_table [1] old_column new_column VARCHAR(50);

Drag options to blanks, or click blank then click option'

AUPDATE COLUMN

BRENAME COLUMN

CMODIFY COLUMN

DCHANGE COLUMN

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'RENAME COLUMN' which is not supported in all SQL dialects.

Omitting the data type when renaming a column.

To rename a column in many SQL databases like MySQL, the syntax is ALTER TABLE my_table CHANGE COLUMN old_column new_column VARCHAR(50);. The keyword CHANGE COLUMN is used along with the new column definition.

3fill in blank

hard

Fix the error in the code to rename a table from users to customers.

DBMS Theory

ALTER TABLE users [1] customers;

Drag options to blanks, or click blank then click option'

ACHANGE TO

BRENAME TO

CMODIFY TO

DUPDATE TO

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'CHANGE TO' which is incorrect for renaming tables.

Forgetting the 'TO' keyword after 'RENAME'.

The correct syntax to rename a table is ALTER TABLE users RENAME TO customers;. Using RENAME TO is the standard and correct keyword.

4fill in blank

hard

Fill both blanks to rename a column address to location with type VARCHAR(100) in the table employees.

DBMS Theory

ALTER TABLE employees [1] address [2] location VARCHAR(100);

Drag options to blanks, or click blank then click option'

ACHANGE COLUMN

BRENAME COLUMN

CTO

DAS

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'RENAME COLUMN' which is not supported in all SQL dialects.

Using 'AS' instead of 'TO' between column names.

The correct syntax to rename a column in many SQL dialects is ALTER TABLE employees CHANGE COLUMN address location VARCHAR(100);. The keywords CHANGE COLUMN are used and the old and new column names are listed consecutively.

5fill in blank

hard

Fill all three blanks to rename a table orders to sales_orders and rename column order_date to sale_date with type DATE.

DBMS Theory

ALTER TABLE [1] [2] sales_orders; ALTER TABLE sales_orders [3] order_date sale_date DATE;

Drag options to blanks, or click blank then click option'

Aorders

BRENAME TO

CTO

DCHANGE COLUMN

Attempts:

3 left

💡 Hint

Common Mistakes

Mixing up the order of commands.

Using incorrect keywords like 'MODIFY' instead of 'CHANGE COLUMN'.

First, rename the table using ALTER TABLE orders RENAME TO sales_orders;. Then rename the column with ALTER TABLE sales_orders CHANGE COLUMN order_date sale_date DATE;. The blanks correspond to the old table name, the rename keyword, and the column rename keyword.

Practice

1. What is the main purpose of the RENAME operation in a database?

easy

A. To change the data type of a column

B. To change the name of a table or column for better clarity

C. To add new rows to a table

D. To delete a table permanently

Solution

1. Step 1: Understand the rename operation

   The rename operation is used to change the name of database objects like tables or columns.

2. Step 2: Identify the purpose of renaming

   Renaming helps improve clarity or update names without changing data or structure.

3. Final Answer:

   To change the name of a table or column for better clarity -> Option B

4. Quick Check:

   Rename = Change name [OK]

Hint: Rename changes names, not data or structure [OK]

Common Mistakes:

• Confusing rename with delete operation
• Thinking rename adds or removes data
• Mixing rename with changing data types

2. Which of the following is the correct SQL syntax to rename a table named Employees to Staff?

easy

A. UPDATE TABLE Employees SET NAME = 'Staff';

B. RENAME TABLE Employees TO Staff;

C. ALTER TABLE Employees RENAME TO Staff;

D. CHANGE TABLE Employees TO Staff;

Solution

1. Step 1: Recall the standard rename table syntax

   The correct syntax uses ALTER TABLE followed by RENAME TO and the new table name.

2. Step 2: Compare options with correct syntax

   ALTER TABLE Employees RENAME TO Staff; matches the correct syntax exactly.

3. Final Answer:

   ALTER TABLE Employees RENAME TO Staff; -> Option C

4. Quick Check:

   ALTER TABLE + RENAME TO = Rename table [OK]

Hint: Use ALTER TABLE with RENAME TO for tables [OK]

Common Mistakes:

• Using UPDATE instead of ALTER TABLE
• Using RENAME TABLE which is not standard SQL
• Using CHANGE TABLE which is invalid

3. Consider the SQL command:
ALTER TABLE Products RENAME COLUMN price TO cost;
What will be the effect of this command?

medium

A. The column price in Products will be renamed to cost

B. The table Products will be renamed to cost

C. The data in price column will be copied to a new column cost

D. An error will occur because RENAME COLUMN is invalid

Solution

1. Step 1: Analyze the command structure

   The command uses ALTER TABLE with RENAME COLUMN, which changes a column's name.

2. Step 2: Identify the target of renaming

   The column named price in Products is renamed to cost, not the table itself.

3. Final Answer:

   The column price in Products will be renamed to cost -> Option A

4. Quick Check:

   RENAME COLUMN changes column name [OK]

Hint: RENAME COLUMN changes only column names [OK]

Common Mistakes:

• Thinking the whole table is renamed
• Assuming data is duplicated
• Believing RENAME COLUMN is invalid syntax

4. Identify the error in the following SQL command:
ALTER TABLE Customers RENAME price TO cost;

medium

A. Table name Customers is invalid

B. No error, command is correct

C. RENAME cannot be used with ALTER TABLE

D. Missing the keyword COLUMN before price

Solution

1. Step 1: Review the syntax for renaming a column

   The correct syntax requires the keyword COLUMN before the old column name.

2. Step 2: Check the given command

   The command misses COLUMN, so it should be: ALTER TABLE Customers RENAME COLUMN price TO cost;

3. Final Answer:

   Missing the keyword COLUMN before price -> Option D

4. Quick Check:

   RENAME COLUMN needs COLUMN keyword [OK]

Hint: Always include COLUMN when renaming columns [OK]

Common Mistakes:

• Omitting COLUMN keyword
• Confusing table rename syntax with column rename
• Assuming RENAME alone works for columns

5. You have a table Orders with columns order_id, cust_id, and date. You want to rename the table to CustomerOrders and rename the column date to order_date. Which sequence of commands correctly performs both renames?

hard

A. ALTER TABLE Orders RENAME TO CustomerOrders; ALTER TABLE CustomerOrders RENAME COLUMN date TO order_date;

B. RENAME TABLE Orders TO CustomerOrders; RENAME COLUMN date TO order_date ON Orders;

C. ALTER TABLE Orders RENAME TO CustomerOrders; ALTER TABLE Orders RENAME COLUMN date TO order_date;

D. ALTER TABLE Orders CHANGE date order_date; RENAME TABLE Orders TO CustomerOrders;

Solution

1. Step 1: Rename the table first

   Use ALTER TABLE Orders RENAME TO CustomerOrders; to rename the table.

2. Step 2: Rename the column on the new table name

   Then rename the column with ALTER TABLE CustomerOrders RENAME COLUMN date TO order_date; because the table name changed.

3. Final Answer:

   ALTER TABLE Orders RENAME TO CustomerOrders; ALTER TABLE CustomerOrders RENAME COLUMN date TO order_date; -> Option A

4. Quick Check:

   Rename table then rename column on new table [OK]

Hint: Rename table first, then rename columns on new table [OK]

Common Mistakes:

• Using old table name after renaming table
• Using non-standard RENAME TABLE syntax
• Using CHANGE instead of RENAME COLUMN