Python MySQL Connectoris a Python driver that helps to integrate Python and MySQL. This Python MySQL library allows the conversion between Python and MySQL data types. MySQL Connector API is implemented using pure Python and does not require any third-party library.
This Python MySQL tutorial will help to learn how to use MySQL with Python from basics to advance, including all necessary functions and queries explained in detail with the help of good Python MySQL examples. So, let's get started.
Installation
To install thePython-mysql-connector module, one must have Python and PIP, preinstalled on their system. If Python and pip are already installed type the below command in the terminal.
pip3 install mysql-connector-python
Note:If Python is not present, go through How to install Python onWindows andLinux? and follow the instructions provided.
Connecting to MySQL Server
We can connect to bothlocalandcloud-based MySQL databases using the connect method of mysql-connector library.
Example:Connecting to Local MySQL Database
Python# importing required librariesimportmysql.connectordataBase=mysql.connector.connect(host="localhost",# Localhost for local connectionuser="user",passwd="password")print(dataBase)# Disconnecting from the serverdataBase.close()
Output:
<mysql.connector.connection_cext.CMySQLConnection object at 0x7f73f0191d00>
Note: For more information, refer toConnect MySQL database using MySQL-Connector Python.
Creating Database
After connecting to the MySQL server let's see how tocreate a MySQL database using Python. For this, we will first create a cursor() object and will then pass the SQL command as a string to the execute() method. The SQL command to create a database is -
CREATE DATABASE DATABASE_NAME
Example: Creating MySQL database with Python
Python# importing required librariesimportmysql.connectordataBase=mysql.connector.connect(host="localhost",user="user",passwd="password")# preparing a cursor objectcursorObject=dataBase.cursor()# creating databasecursorObject.execute("CREATE DATABASE gfg")Output:
Creating Tables
Forcreating tables we will follow the similar approach of writing the SQL commands as strings and then passing it to the execute() method of the cursor object. SQL command for creating a table is -
CREATE TABLE
(
column_name_1 column_Data_type,
column_name_2 column_Data_type,
:
:
column_name_n column_Data_type
);
Example: Creating MySQL table using Python
Python# importing required librariesimportmysql.connectordataBase=mysql.connector.connect(host="localhost",user="user",passwd="password",database="gfg")# preparing a cursor objectcursorObject=dataBase.cursor()# creating tablestudentRecord="""CREATE TABLE STUDENT ( NAME VARCHAR(20) NOT NULL, BRANCH VARCHAR(50), ROLL INT NOT NULL, SECTION VARCHAR(5), AGE INT )"""# table createdcursorObject.execute(studentRecord)# disconnecting from serverdataBase.close()
Output:
Insert Data into Tables
Toinsert data into the MySQL tableInsert intoquery is used.
Syntax:
INSERT INTO table_name (column_names) VALUES (data)
Example 1: Inserting Single Row
Python# importing required librariesimportmysql.connectordataBase=mysql.connector.connect(host="localhost",user="user",passwd="password",database="gfg")# preparing a cursor objectcursorObject=dataBase.cursor()sql="INSERT INTO STUDENT (NAME, BRANCH, ROLL, SECTION, AGE)\VALUES (%s,%s,%s,%s,%s)"val=("Ram","CSE","85","B","19")cursorObject.execute(sql,val)dataBase.commit()# disconnecting from serverdataBase.close()Output:
Example 2: Inserting Multiple Rows
To insert multiple values at once, executemany() method is used. This method iterates through the sequence of parameters, passing the current parameter to the execute method.
Python# importing required librariesimportmysql.connectordataBase=mysql.connector.connect(host="localhost",user="user",passwd="password",database="gfg")# preparing a cursor objectcursorObject=dataBase.cursor()sql="INSERT INTO STUDENT (NAME, BRANCH, ROLL, SECTION, AGE)\VALUES (%s,%s,%s,%s,%s)"val=[("Nikhil","CSE","98","A","18"),("Nisha","CSE","99","A","18"),("Rohan","MAE","43","B","20"),("Amit","ECE","24","A","21"),("Anil","MAE","45","B","20"),("Megha","ECE","55","A","22"),("Sita","CSE","95","A","19")]cursorObject.executemany(sql,val)dataBase.commit()# disconnecting from serverdataBase.close()Output:
Fetching Data
We can use theselect query on the MySQL tables in the following ways -
- In order to select particular attribute columns from a table, we write the attribute names.
SELECT attr1, attr2 FROM table_name
- In order to select all the attribute columns from a table, we use the asterisk ‘*’ symbol.
SELECT * FROM table_name
Example: Select data from MySQL tableusing Python
Python# importing required librariesimportmysql.connectordataBase=mysql.connector.connect(host="localhost",user="user",passwd="password",database="gfg")# preparing a cursor objectcursorObject=dataBase.cursor()query="SELECT NAME, ROLL FROM STUDENT"cursorObject.execute(query)myresult=cursorObject.fetchall()forxinmyresult:print(x)# disconnecting from serverdataBase.close()
Output:
Where Clause
Where clause is used in MySQL database to filter the data as per the condition required. You can fetch, delete or update a particular set of data in MySQL database by using where clause.
Syntax:
SELECT column1, column2, …. columnN FROM [TABLE NAME] WHERE [CONDITION];
Example: Where clause in MySQL using Python
Python# importing required librariesimportmysql.connectordataBase=mysql.connector.connect(host="localhost",user="user",passwd="password",database="gfg")# preparing a cursor objectcursorObject=dataBase.cursor()query="SELECT * FROM STUDENT where AGE >=20"cursorObject.execute(query)myresult=cursorObject.fetchall()forxinmyresult:print(x)# disconnecting from serverdataBase.close()
Output:
('Rohan', 'MAE', 43, 'B', 20)
('Amit', 'ECE', 24, 'A', 21)
('Anil', 'MAE', 45, 'B', 20)
('Megha', 'ECE', 55, 'A', 22)
Order By Clause
OrderBy is used to arrange the result set in either ascending or descending order. By default, it is always in ascending order unless “DESC” is mentioned, which arranges it in descending order. “ASC” can also be used to explicitly arrange it in ascending order. But, it is generally not done this way since default already does that.
Syntax:
SELECT column1, column2
FROM table_name
ORDER BY column_name ASC|DESC;
Example: Order By clause in MySQL using Python
Python# importing required librariesimportmysql.connectordataBase=mysql.connector.connect(host="localhost",user="user",passwd="password",database="gfg")# preparing a cursor objectcursorObject=dataBase.cursor()query="SELECT * FROM STUDENT ORDER BY NAME DESC"cursorObject.execute(query)myresult=cursorObject.fetchall()forxinmyresult:print(x)# disconnecting from serverdataBase.close()
Output:
Limit Clause
TheLimit clause is used in SQL to control or limit the number of records in the result set returned from the query generated. By default, SQL gives out the required number of records starting from the top but it allows the use of OFFSET keyword. OFFSET allows you to start from a custom row and get the required number of result rows.
Syntax:
SELECT * FROM tablename LIMIT limit;
SELECT * FROM tablename LIMIT limit OFFSET offset;
Example: Limit Clause in MySQL using Python
Python# importing required librariesimportmysql.connectordataBase=mysql.connector.connect(host="localhost",user="user",passwd="password",database="gfg")# preparing a cursor objectcursorObject=dataBase.cursor()query="SELECT * FROM STUDENT LIMIT 2 OFFSET 1"cursorObject.execute(query)myresult=cursorObject.fetchall()forxinmyresult:print(x)# disconnecting from serverdataBase.close()
Output:
('Nikhil', 'CSE', 98, 'A', 18)
('Nisha', 'CSE', 99, 'A', 18)
Update Data
Theupdate query is used to change the existing values in a database. By using update a specific value can be corrected or updated. It only affects the data and not the structure of the table. The basic advantage provided by this command is that it keeps the table accurate.
Syntax:
UPDATE tablename
SET ="new value"
WHERE ="old value";
Example: Update MySQL table using Python
Python# importing required librariesimportmysql.connectordataBase=mysql.connector.connect(host="localhost",user="user",passwd="password",database="gfg")# preparing a cursor objectcursorObject=dataBase.cursor()query="UPDATE STUDENT SET AGE = 23 WHERE Name ='Ram'"cursorObject.execute(query)dataBase.commit()# disconnecting from serverdataBase.close()
Output:
Delete Data from Table
We can use theDelete query to delete data from the table in MySQL.
Syntax:
DELETE FROM TABLE_NAME WHERE ATTRIBUTE_NAME = ATTRIBUTE_VALUE
Example: Delete Data from MySQL table using Python
Python# importing required librariesimportmysql.connectordataBase=mysql.connector.connect(host="localhost",user="user",passwd="password",database="gfg")# preparing a cursor objectcursorObject=dataBase.cursor()query="DELETE FROM STUDENT WHERE NAME = 'Ram'"cursorObject.execute(query)dataBase.commit()# disconnecting from serverdataBase.close()
Output:
Drop Tables
Drop command affects the structure of the table and not data. It is used to delete an already existing table. For cases where you are not sure if the table to be dropped exists or not DROP TABLE IF EXISTS command is used. Both cases will be dealt with in the following examples.
Syntax:
DROP TABLE tablename;
DROP TABLE IF EXISTS tablename;
At first, let's see the list of tables in our database.
We can see that there are two tables for students, so let's drop the second table.
Example 1: Drop Table in MySQL using Python
Python# importing required librariesimportmysql.connectordataBase=mysql.connector.connect(host="localhost",user="user",passwd="password",database="gfg")# preparing a cursor objectcursorObject=dataBase.cursor()query="DROP TABLE Student;"cursorObject.execute(query)dataBase.commit()# disconnecting from serverdataBase.close()
Output:
Example 2: Drop Table if exists
Python# importing required librariesimportmysql.connectordataBase=mysql.connector.connect(host="localhost",user="user",passwd="password",database="gfg")# preparing a cursor objectcursorObject=dataBase.cursor()query="Drop Table if exists Employee;"cursorObject.execute(query)dataBase.commit()# disconnecting from serverdataBase.close()
The above example, will not create any error and output because we have used the Drop Table is exists query. If we will simply use the Drop table Employee thenProgrammingError: 1051 (42S02): Unknown table 'gfg.Employee' is raised.
Python MySQL Exercises
Working With Tables
Working on Columns
Python MySQL Applications and Projects