MySql Database code example

Example 1: create database mysql

CREATE DATABASE `mydb`;

CREATE TABLE `my_table`
(
	my_table_id INT AUTO_INCREMENT,
    my_table_name VARCHAR(30) NOT NULL,
    my_foreign_key INT NOT NULL,
    my_tb_created TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
  	my_tb_updated TIMESTAMP DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP, ,
    # Any other properties here
    PRIMARY KEY(my_table_id),
    CONSTRAINT fk_name_of_parent_table
    FOREIGN KEY(my_foreign_key) REFERENCES parent_table(parent_table_column)
);

SHOW DATABASES;

Example 2: mean mysql

avg(column)

Example 3: what is mysql?

MySQL is an open source DBMS which is built, supported and distributed by MySQL(ORACLE).

Example 4: python and mysql connectivity

import pymysql

############### CONFIGURE THIS ###################
# Open database connection
db = pymysql.connect("database_host","username","password","database_name")
##################################################

# prepare a cursor object using cursor() method
cursor = db.cursor()

# execute SQL query using execute() method.
cursor.execute("SELECT VERSION()")

# Fetch a single row using fetchone() method.
data = cursor.fetchone()
print ("Database version : {0}".format(data))

# disconnect from server
db.close()

Example 5: mysqli database

<?php
$mysqli = new mysqli("localhost", "my_user", "my_password", "test");

/* Vérification de la connexion */
if (mysqli_connect_errno()) {
    printf("Échec de la connexion : %s\n", mysqli_connect_error());
    exit();
}

/* Retourne le nom de la base de données courante */
if ($result = $mysqli->query("SELECT DATABASE()")) {
    $row = $result->fetch_row();
    printf("La base de données courante est %s.\n", $row[0]);
    $result->close();
}

/* Change la base de données en "world" */
$mysqli->select_db("world");

/* Retourne le nom de la base de données courante */
if ($result = $mysqli->query("SELECT DATABASE()")) {
    $row = $result->fetch_row();
    printf("La base de données courante est %s.\n", $row[0]);
    $result->close();
}

$mysqli->close();
?>

Example 6: MYSQL

GRANT CREATE ON *.* TO 'testuser'@'localhost';