Python Database API ( Application Program Interface ) is the Database interface for the standard Python. This standard is adhered to by most Python Database interfaces. There are various Database servers supported by Python Database such as MySQL, GadFly, mySQL, PostgreSQL, Microsoft SQL Server 2000, Informix, Interbase, Oracle, Sybase etc. To connect with MySQL database server from Python, we need to import the mysql.connector module. Below is a program to connect with MySQL database Lazyroar.
Python
# importing required library import mysql.connector # connecting to the database dataBase = mysql.connector.connect( host = "localhost", user = "user", passwd = "pswrd", database = "Lazyroar" ) # preparing a cursor object cursorObject = dataBase.cursor() # disconnecting from server dataBase.close() |
The above program illustrates the connection with the MySQL database Lazyroar in which host-name is localhost, the username is user and password is pswrd.
Select Query
After connecting with the database in MySQL we can select queries from the tables in it. Syntax:
- 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 1: Let’s consider the table looks like this – Below is a program to select a query from the table in the database.
Python
# importing required library import mysql.connector # connecting to the database dataBase = mysql.connector.connect( host = "localhost", user = "user", passwd = "pswrd", database = "Lazyroar" ) # preparing a cursor object cursorObject = dataBase.cursor() print ("Displaying NAME and ROLL columns from the STUDENT table:") # selecting query query = "SELECT NAME, ROLL FROM STUDENT" cursorObject.execute(query) myresult = cursorObject.fetchall() for x in myresult: print (x) # disconnecting from server dataBase.close() |
Output: Example 2: Let us look at another example for selecting queries in a table.
Python
# importing required library import mysql.connector # connecting to the database dataBase = mysql.connector.connect( host = "localhost", user = "user", passwd = "pswrd", database = "Lazyroar" ) # preparing a cursor object cursorObject = dataBase.cursor() print ("Displaying NAME and ROLL columns from the STUDENT table:") # selecting query query = "SELECT * FROM STUDENT" cursorObject.execute(query) myresult = cursorObject.fetchall() for x in myresult: print (x) # disconnecting from server dataBase.close() |
Output: