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To create a table in MySQL, use the "CREATE TABLE" statement. Make sure you define the name of the database when you create the connection
Create a table named "customers":
Formula
import mysql.connector mydb = mysql.connector.connect(host="localhost", user=" yourusername ", password=" yourpassword ", database="mydatabase" )
Formula
mycursor = mydb.cursor()mycursor.execute("CREATE TABLE customers (name VARCHAR(255), address VARCHAR(255))") If the above code was executed with no errors, you have now successfully created a table.
You can check if a table exist by listing all tables in your database with the "SHOW TABLES" statement:
Return a list of your system's databases:
Formula
import mysql.connector mydb = mysql.connector.connect(host="localhost", user=" yourusername ", password=" yourpassword ", database="mydatabase" )
Formula
mycursor = mydb.cursor()mycursor.execute("SHOW TABLES") for x in mycursor:
print(x)When creating a table, you should also create a column with a unique key for each record. This can be done by defining a PRIMARY KEY. We use the statement "INT AUTO_INCREMENT PRIMARY KEY" which will insert a unique number for each record. Starting at 1, and increased by one for each record.
Create primary key when creating the table:
Formula
import mysql.connector mydb = mysql.connector.connect(host="localhost", user=" yourusername ", password=" yourpassword ", database="mydatabase" )
Formula
mycursor = mydb.cursor()mycursor.execute("CREATE TABLE customers (id INT AUTO_INCREMENT PRIMARY KEY, name VARCHAR(255), address VARCHAR(255))") If the table already exists, use the ALTER TABLE keyword:
Create primary key on an existing table:
Formula
import mysql.connector mydb = mysql.connector.connect(host="localhost", user=" yourusername ", password=" yourpassword ", database="mydatabase" )
Formula
mycursor = mydb.cursor()mycursor.execute("ALTER TABLE customers ADD COLUMN id INT AUTO_INCREMENT
PRIMARY KEY")