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MySQL Alter Table Statement Exercises: Drop the column city from the table locations

MySQL Alter Table Statement: Exercise-6 with Solution

Write a MySQL statement to drop the column city from the table locations.

Here is the structure of the table locations.

mysql> SHOW COLUMNS FROM locations;
+----------------+--------------+------+-----+---------+-------+
| Field          | Type         | Null | Key | Default | Extra |
+----------------+--------------+------+-----+---------+-------+
| LOCATION_ID    | decimal(4,0) | YES  |     | NULL    |       |
| STREET_ADDRESS | varchar(40)  | YES  |     | NULL    |       |
| POSTAL_CODE    | varchar(12)  | YES  |     | NULL    |       |
| CITY           | varchar(30)  | YES  |     | NULL    |       |
| STATE_PROVINCE | varchar(25)  | YES  |     | NULL    |       |
| COUNTRY_ID     | varchar(2)   | YES  |     | NULL    |       |
+----------------+--------------+------+-----+---------+-------+

Code:

 -- This SQL statement is used to alter the 'locations' table by removing a column.
-- The 'city' column is being dropped from the table.

ALTER TABLE locations

-- Drop the 'city' column from the 'locations' table.
DROP city;

Let execute the above code in MySQL command prompt

Now see the structure of the table locations after alteration.

mysql> SHOW COLUMNS FROM locations;
+----------------+--------------+------+-----+---------+-------+
| Field          | Type         | Null | Key | Default | Extra |
+----------------+--------------+------+-----+---------+-------+
| LOCATION_ID    | decimal(4,0) | YES  |     | NULL    |       |
| STREET_ADDRESS | varchar(40)  | YES  |     | NULL    |       |
| POSTAL_CODE    | varchar(12)  | YES  |     | NULL    |       |
| STATE_PROVINCE | varchar(25)  | YES  |     | NULL    |       |
| COUNTRY_ID     | varchar(2)   | YES  |     | NULL    |       |
+----------------+--------------+------+-----+---------+-------+

Explanation:

Here's a brief explanation of the above MySQL code:

  • ALTER TABLE locations: This part of the statement indicates that you want to make changes to the structure of the 'locations' table.
  • DROP city;: This specifies the action to be taken. It removes (drops) the 'city' column from the 'locations' table.

The above result shows that there is no 'city' column; it has been dropped from the table locations.

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Previous: Write a SQL statement change the data type of the column country_id to integer in the table locations.
Next: Write a SQL statement to change the name of the column state_province to state, keeping the data type and size same.

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