I'm wondering if there is any built-in way in Python to test a MySQL server connection. I know I can use PyMySQL, MySQLdb, and a few others, but if the user does not already have these dependencies installed my script will not work? How can I write a Python script to test a MySQL connection without requiring external dependencies?
Python distributions do not include support for MySQL, which is only available by installing a third-party module such as PyMySQL or MySQLdb. The only relational support included in Python is for the SQLite database (in the shape of the sqlite3 module).
There is, however, nothing to stop you distributing a third-party module as a part of your application, thereby including the support your project requires. PyMySQL would probably be the best choice because, being pure Python, it will run on any platform and give you best portability.
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I wrote a python script that requires the use of a postgresql DB. For test purpose, I installed the postgresql DB manually, and the DB that comes with that. The script connects to it and make its job.
My question is about packaging : what is the best solution for the user to install this script, along with the DB and its schema juste by typing pip install xxx ?
Is that possible ?
Thanks
Postgres is great but often you can get away with SQLite. It's part of the standard library and comes bundled with Python
I want to implement a simple application (for Windows), mainly for data collection and I should be able to run some queries.
I can produce an exe file from the python code, but I don't want to install the database separately, rather I'd include it in an installer. I think some other applications do the same or they require MySQL to be installed -- not in development mode -- since I saw in Windows' Programs and Features that there are some MySQL installations.
So my question is: Is there a way to use MySQL or a specific preparation method of an application so I am able to use some database operations inclusive saving data? Remark: any database would work, I was referring to MySQL because I suspect I saw some examples.
You could use Pyinstaller to make an exe out of your database and Python file. Python natively supports sqlite so you don't have to install anything extra if you use that.
I have two RHEL servers running Python 2.4 and 2.6 separately. There is an Oracle database on the other server I need to access.
I was trying to install cx_oracle on my RHEL server but found out that the Oracle client must be installed first.
The problem is, I don’t have permission to install Oracle's client on both RHEL servers. On the same servers, a Perl program can connect to the Oracle db using:
DBI->connect("dbi:Oracle:host=myhost.prod.com;sid=prddb",'username','password')
Can Python do the same without installing cx_oracle and the Oracle client? Or are there any suggestions about how to write a module myself to do the same thing?
Thanks in advance!
An excerpt from https://forum.omz-software.com/topic/184/oracle-database:
There's no pure python client for Oracle and likely never will be. Even wonderful third-party toolsets like SQLalchemy still rely on cx_Oracle underneath to do the actual communication to the Oracle database servers.
—also, deciding by Google, the answer is no: there do not seem to be any pure Python Oracle clients in existence as of today.
Usually, all you need are the libraries, which don't necessarily require sudo rights. Extract them to a place the software will be able to read from and set the following environment variables accordingly:
ORACLE_HOME=path/to/where/you/extracted/libs
TNS_ADMIN=path/to/tnsnames.ora
I have had best luck skipping tnsnames, and just specifying the host, port, etc in the connection, but it's quite possible you'll need it for cx_oracle...I don't remember from when I used it ages ago.
if you don't want use cx_Oracle you should use expect scripting. ( for python pexpect). But you need to be carefully for handle all expectations.
I'd like to query a MySQL database using Python, but evidently the MySQLdb package requires a huge toolchain of MySQL stuff to be separately installed.
How can I query a MySQL database using a Python script without installing a bunch of unnecessary MySQL stuff, including conferring MySQL server capability on the client machine?
I don't love Perl, but it appears that the DBI package allows a Perl script to interface with MySQL without any MySQL stuff external to the package. I'm looking for something similar for Python.
You need to find a pure mysql python library. I have seen a couple over the last couple months. A quick google search yoelded pymysql. It has a large following on github. It looks promising. Pymysql is a pure python mysql client.
https://github.com/petehunt/PyMySQL
MySQLdb is just one of the available database drivers. It requires all that extra installation stuff, because it compiles c extensions and is one of the faster options.
There are a handful of other database drivers, some of which are pure-python.
The SqlAlchemy project has one of the more up-to-date collections of database drivers:
http://docs.sqlalchemy.org/en/latest/core/engines.html
PyMysql is a pure python driver, so it won't need to be built against the local MySql library.
I have a written a very small web-based survey using cgi with python(This is my first web app. ).The questions are extracted from a MySQL database table and the results are supposed to be saved in the same database. I have created the database along with its table locally. My app works fine on my local computer(localhost). To create db,table and other transaction with the MySQL i had to do import MySQLdb in my code.
Now I want to upload everything on my personal hosting. As far as I know my hosting supports Python,CGI and has MySQL database. And I know that I have to change some parameters in the connection string in my code, so I can connect to the database, but I have two problems:
I remember that I installed MySQLdb as an extra to my Python, and in my code i am using it, how would I know that my hosting's python interpretor has this installed, or do I even need it, do I have to use another library?
How do I upload my database onto my hosting?
Thanks
If you have shell access, you can fire up the python interpreter by running python and type import MySQLdb at the >>> prompt. If you get no errors in return, then its installed.
Likewise, if you have shell access, this page will help you with importing and exporting using the mysql command. I found it by googleing "import export mysql".
You can write a simple script like
import MySQLdb and catch any errors
to see if the required package is
installed. If this fails you can ask
the hosting provider to install your
package, typically via a ticket
The hosting providers typically also provide URL's to connect to the MySQL tables they provision for you, and some tools like phpmyadmin to load database dumps into the hosted MySQL instance
To check if MySQLdb library is installed on your hosting, simply open a python shell and type: import MySQLdb. If everthing goes ok, you're readt to go. If you get: ImportError: No module named MySQLdb, that means the the library is not installed and you nedd to install it.
You need that library or some library that provides similar support, because Python does not support native access to MySQL databases.
To transfer you database to your hosting check mysqldump.