Python MySQL - Drop Table

Advertisements

Previous Page
Next Page  

You can remove an entire table using the DROP TABLE statement. You just need to specify the name of the table you need to delete.

Syntax

Following is the syntax of the DROP TABLE statement in MySQL −

DROP TABLE table_name;

Example

Before deleting a table get the list of tables using the SHOW TABLES statement as follows −

mysql> SHOW TABLES;
+-----------------+
| Tables_in_mydb  |
+-----------------+
| contact         |
| cricketers_data |
| employee        |
| sample          |
| tutorials       |
+-----------------+
5 rows in set (0.00 sec)

Following statement removes the table named sample from the database completely −

mysql> DROP TABLE sample;
Query OK, 0 rows affected (0.29 sec)

Since we have deleted the table named sample from MySQL, if you get the list of tables again you will not find the table name sample in it.

mysql> SHOW TABLES;
+-----------------+
| Tables_in_mydb  |
+-----------------+
| contact         |
| cricketers_data | 
| employee        |
| tutorials       |
+-----------------+
4 rows in set (0.00 sec)

Removing a Table Using Python

You can drop a table whenever you need to, using the DROP statement of MYSQL, but you need to be very careful while deleting any existing table because the data lost will not be recovered after deleting a table.

To drop a table from a MYSQL database using python invoke the execute() method on the cursor object and pass the drop statement as a parameter to it.

Example

Following table drops a table named EMPLOYEE from the database.

import mysql.connector
#establishing the connection conn = mysql.connector.connect(
   user='root', password='password', host='127.0.0.1', database='mydb'
)

#Creating a cursor object using the cursor() method cursor = conn.cursor()

#Retrieving the list of tables print("List of tables in the database: ")   
   cursor.execute("SHOW Tables") print(cursor.fetchall())

#Doping EMPLOYEE table if already exists cursor.execute("DROP TABLE EMPLOYEE") 
   print("Table dropped... ")

#Retrieving the list of tables print(
   "List of tables after dropping the EMPLOYEE table: "
) 
cursor.execute("SHOW Tables") print(cursor.fetchall())

#Closing the connection 
conn.close()

Output

List of tables in the database:
[('employee',), ('employeedata',), ('sample',), ('tutorials',)]
Table dropped...
List of tables after dropping the EMPLOYEE table:
[('employeedata',), ('sample',), ('tutorials',)]

Drop Table Only if Exists

If you try to drop a table which does not exist in the database, an error occurs as −

mysql.connector.errors.ProgrammingError: 1051 (42S02): Unknown table 'mydb.employee'

You can prevent this error by verifying whether the table exists before deleting, by adding the IF EXISTS to the DELETE statement.

Example

import mysql.connector
#establishing the connection
conn = mysql.connector.connect(
   user='root', password='password', host='127.0.0.1', database='mydb'
)

#Creating a cursor object using the cursor() method
cursor = conn.cursor()

#Retrieving the list of tables
print("List of tables in the database: ")
cursor.execute("SHOW Tables")
print(cursor.fetchall())

#Doping EMPLOYEE table if already exists
cursor.execute("DROP TABLE IF EXISTS EMPLOYEE")
print("Table dropped... ")

#Retrieving the list of tables
print("List of tables after dropping the EMPLOYEE table: ")
cursor.execute("SHOW Tables")
print(cursor.fetchall())

#Closing the connection
conn.close()

Output

List of tables in the database:
[('employeedata',), ('sample',), ('tutorials',)]
Table dropped...
List of tables after dropping the EMPLOYEE table:
[('employeedata',), ('sample',),
('tutorials',)]
Advertisements