mysql_commando

MySQL driver that calls database on command line

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Python

mysql_commando

Installing a MySQL driver on a machine is sometime a pain, or even impossible.
Furthermore you may want to distribute self contained scripts that access MySQL
without having to ask for additional software installation.

mysql_commando is a pure Python MySQL driver that calls MySQL running
the client on the command line. It was designed so that you may use it by
dropping its module in your source tree or even copy its class in your own
source code.

Installation

To install mysql_commando, you may use one of the following methods:

  • Extract its classes MysqlCommando and MysqlException from tarball (in file
    mysql_commando/mysql_commando.py) and put it in your own source code.
  • Drop its module (file mysql_commando/mysql_commando.py in the tarball)
    in your source directory.
  • Install it using PIP, typing pip install mysql_commando.
  • Install from tarball typing python setup.py install.

The Apache license grants you a right to use this driver in any of your project
(even commercial) provided that you mention that you are using
mysql_commando in your copyright notice.

Usage

You can use this driver in your code just like so:

from mysql_commando import MysqlCommando

mysql = MysqlCommando(hostname='localhost', database='test',
                      username='test', password='test')
result = mysql.run_query("SHOW DATABASES")
print resul

When query returns nothing (after an INSERT for instance), method
run_query() will return None. If query returns a result set, this will
be a tuple of dictionaries. For instance, previous sample code could print:

({'Database': 'information_schema'}, {'Database': 'mysql'})

Instead of running a query you may run a script as follows:

result = mysql.run_script('my_script.sql')

Parameters

You can have values such as %(foo)s in you query that will be replaced
with corresponding value of the parameters dictionary. For instance:

from mysql_commando import MysqlCommando

mysql = MysqlCommando(hostname='localhost', database='test',
                      username='test', password='test')
parameters = {'name': 'reglisse'}
result = mysql.run_query(query="SELECT * FROM animals WHERE name=%(name)s",
                         parameters=parameters)
print result

You may not provide parameters running a script. To do so, call run_query()
with parameters passing query open('my_script.sql').read().

Result set types

mysql_commando performs auto casting before returning result sets. As it
calls MySQL on command line, every value in the result set is a string. For
convenience, it casts integers, floats, dates and NULL into native Python types.

There are situations where this might not be accurate. For instance, if a column
is of SQL type VARCHAR(10) and contain phone numbers, all its values will be
casted to Python integers. It should not because phone numbers can start with
0 and it should not be turned to integer.

To avoid this, you may pass cast=False when calling run_query() or
run_script(), like so:

from mysql_commando import MysqlCommando

mysql = MysqlCommando(hostname='localhost', database='test',
                      username='test', password='test')
result = mysql.run_query("SELECT phone FROM users WHERE name='bob')", cast=False)
print result

You may also disable casting when instantiating the driver, passing
cast=False to the constructor. This casting configuration will apply on all
calls to run_query() or run_script() except if you pass a different
value while calling these methods.

Last insert ID

To get the ID of the last INSERT of a given query, you can pass
last_insert_id=True while calling run_query(), as follows:

query = "INSERT INTO animals (name, age) VALUES ('Reglisse', 14)"
id = mysql.run_query(query, last_insert_id=True)
print id

This will return the last INSERT ID as an integer.

If you need to get ID of the last INSERT running a script, just add a call to
MySQL function last_insert_id() like so:

INSERT INTO animals (name, age) VALUES ('Reglisse', 14);
SELECT last_insert_id() AS id;

While you run this script, this will return the ID of your last INSERT:

({'id': 1},)

Note

This module is not intended to replace MySQLdb that you SHOULD use if you can
install it on the target machine.

Enjoy!