sql.py

# coding=utf-8

import mysql.connector
from configparser import ConfigParser
from mysql.connector import MySQLConnection, Error



def old_connect():
    """ Connect to MySQL database """
    try:
        conn = mysql.connector.connect(host='localhost',
                                       database='python_mysql',
                                       user='root',
                                       password='secret')
        if conn.is_connected():
            print('Connected to MySQL database')
    except Error as e: print(e)
    finally: conn.close()


def connect():
    """ Connect to MySQL database """
    db_config = read_db_config()

    try:
        print('Connecting to MySQL database...')
        conn = MySQLConnection(**db_config)

        if conn.is_connected():
            print('connection established.')
        else:
            print('connection failed.')

    except Error as error:
        print(error)

    finally:
        conn.close()
        print('Connection closed.')


def read_db_config(filename='sql_config.ini', section='mysql'):
    """ Read database configuration file and return a dictionary object
    :param filename: name of the configuration file
    :param section: section of database configuration
    :return: a dictionary of database parameters
    """
    # create parser and read ini configuration file
    parser = ConfigParser()
    parser.read(filename)

    # get section, default to mysql
    db = {}
    if parser.has_section(section):
        items = parser.items(section)
        for item in items:
            db[item[0]] = item[1]
    else:
        raise Exception('{0} not found in the {1} file'.format(section, filename))

    return db


def query_with_fetchone():
    try:
        dbconfig = read_db_config()
        conn = MySQLConnection(**dbconfig)
        cursor = conn.cursor()
        cursor.execute("SELECT * FROM books")

        row = cursor.fetchone()

        while row is not None:
            print(row)
            row = cursor.fetchone()

    except Error as e:
        print(e)

    finally:
        cursor.close()
        conn.close()


def query_with_fetchall():
    try:
        dbconfig = read_db_config()
        conn = MySQLConnection(**dbconfig)
        cursor = conn.cursor()
        cursor.execute("SELECT * FROM books")
        rows = cursor.fetchall()

        print('Total Row(s):', cursor.rowcount)
        for row in rows:
            print(row)

    except Error as e:
        print(e)

    finally:
        cursor.close()
        conn.close()


def iter_row(cursor, size=10):
    while True:
        rows = cursor.fetchmany(size)
        if not rows:
            break
        for row in rows:
            yield row
def query_with_fetchmany():
    try:
        dbconfig = read_db_config()
        conn = MySQLConnection(**dbconfig)
        cursor = conn.cursor()

        cursor.execute("SELECT * FROM books")

        for row in iter_row(cursor, 10):
            print(row)

    except Error as e:
        print(e)

    finally:
        cursor.close()
        conn.close()


def insert_book(title, isbn):
    query = "INSERT INTO books(title,isbn) VALUES(%s,%s)"
    args = (title, isbn)

    try:
        db_config = read_db_config()
        conn = MySQLConnection(**db_config)

        cursor = conn.cursor()
        cursor.execute(query, args)

        if cursor.lastrowid:
            print('last insert id', cursor.lastrowid)
        else:
            print('last insert id not found')

        conn.commit()
    except Error as error:
        print(error)

    finally:
        cursor.close()
        conn.close()
'''
def main():
   insert_book('A Sudden Light','9781439187036')
'''

def insert_books(books):
    query = "INSERT INTO books(title,isbn) " \
            "VALUES(%s,%s)"

    try:
        db_config = read_db_config()
        conn = MySQLConnection(**db_config)

        cursor = conn.cursor()
        cursor.executemany(query, books)

        conn.commit()
    except Error as e:
        print('Error:', e)

    finally:
        cursor.close()
        conn.close()
'''
def main():
    books = [('Harry Potter And The Order Of The Phoenix', '9780439358071'),
             ('Gone with the Wind', '9780446675536'),
             ('Pride and Prejudice (Modern Library Classics)', '9780679783268')]
    insert_books(books)
'''


def update_book(book_id, title):
    # read database configuration
    db_config = read_db_config()

    # prepare query and data
    query = """ UPDATE books
                SET title = %s
                WHERE id = %s """

    data = (title, book_id)

    try:
        conn = MySQLConnection(**db_config)

        # update book title
        cursor = conn.cursor()
        cursor.execute(query, data)

        # accept the changes
        conn.commit()

    except Error as error:
        print(error)

    finally:
        cursor.close()
        conn.close()




def delete_book(book_id):
    db_config = read_db_config()

    query = "DELETE FROM books WHERE id = %s"

    try:
        # connect to the database server
        conn = MySQLConnection(**db_config)

        # execute the query
        cursor = conn.cursor()
        cursor.execute(query, (book_id,))

        # accept the change
        conn.commit()

    except Error as error:
        print(error)

    finally:
        cursor.close()
        conn.close()



def read_file(filename):
    with open(filename, 'rb') as f:
        photo = f.read()
    return photo
def update_blob(author_id, filename):
    # read file
    data = read_file(filename)

    # prepare update query and data
    query = "UPDATE authors " \
            "SET photo = %s " \
            "WHERE id  = %s"

    args = (data, author_id)

    db_config = read_db_config()

    try:
        conn = MySQLConnection(**db_config)
        cursor = conn.cursor()
        cursor.execute(query, args)
        conn.commit()
    except Error as e:
        print(e)
    finally:
        cursor.close()
        conn.close()




if __name__ == '__main__':

     read_db_config()
     connect()
     query_with_fetchall()