The JayDeBeApi module allows you to connect from Python code to databases using Java JDBC. It provides a Python DB-API v2.0 to that database.
It works on ordinary Python (cPython) using the JPype Java integration or on Jython to make use of the Java JDBC driver.
In contrast to zxJDBC from the Jython project JayDeBeApi let's you access a database with Jython AND Python with only minor code modifications. JayDeBeApi's future goal is to provide a unique and fast interface to different types of JDBC-Drivers through a flexible plug-in mechanism.
You can get and install JayDeBeApi with pip
$ pip install JayDeBeApi
If you want to install JayDeBeApi in Jython make sure to have pip or EasyInstall available for it.
Or you can get a copy of the source by cloning from the JayDeBeApi github project and install with
$ python setup.py install
or if you are using Jython use
$ jython setup.py install
It has been tested with Jython 2.7.2.
If you are using cPython ensure that you have installed JPype properly. It has been tested with JPype1 0.6.3 and 0.7.5 for Python 3 and with JPype1 0.6.3 and 0.7.0 for Python 2.7. Older JPype installations may cause problems.
Basically you just import the jaydebeapi
Python module and execute
the connect
method. This gives you a DB-API conform connection to
the database.
The first argument to connect
is the name of the Java driver
class. The second argument is a string with the JDBC connection
URL. Third you can optionally supply a sequence consisting of user and
password or alternatively a dictionary containing arguments that are
internally passed as properties to the Java
DriverManager.getConnection
method. See the Javadoc of
DriverManager
class for details.
The next parameter to connect
is optional as well and specifies
the jar-Files of the driver if your classpath isn't set up
sufficiently yet. The classpath set in CLASSPATH
environment
variable will be honored. See the documentation of your Java runtime
environment.
Here is an example:
>>> import jaydebeapi
>>> conn = jaydebeapi.connect("org.hsqldb.jdbcDriver",
... "jdbc:hsqldb:mem:.",
... ["SA", ""],
... "/path/to/hsqldb.jar",)
>>> curs = conn.cursor()
>>> curs.execute('create table CUSTOMER'
... '("CUST_ID" INTEGER not null,'
... ' "NAME" VARCHAR(50) not null,'
... ' primary key ("CUST_ID"))'
... )
>>> curs.execute("insert into CUSTOMER values (?, ?)", (1, 'John'))
>>> curs.execute("select * from CUSTOMER")
>>> curs.fetchall()
[(1, u'John')]
>>> curs.close()
>>> conn.close()
If you're having trouble getting this work check if your JAVA_HOME
environment variable is set correctly. For example I have to set it on
my Ubuntu machine like this
$ JAVA_HOME=/usr/lib/jvm/java-8-openjdk python
An alternative way to establish connection using connection properties:
>>> conn = jaydebeapi.connect("org.hsqldb.jdbcDriver",
... "jdbc:hsqldb:mem:.",
... {'user': "SA", 'password': "",
... 'other_property': "foobar"},
... "/path/to/hsqldb.jar",)
Also using the with
statement might be handy:
>>> with jaydebeapi.connect("org.hsqldb.jdbcDriver",
... "jdbc:hsqldb:mem:.",
... ["SA", ""],
... "/path/to/hsqldb.jar",) as conn:
... with conn.cursor() as curs:
... curs.execute("select count(*) from CUSTOMER")
... curs.fetchall()
[(1,)]
In theory every database with a suitable JDBC driver should work. It is confirmed to work with the following databases:
- SQLite
- Hypersonic SQL (HSQLDB)
- IBM DB2
- IBM DB2 for mainframes
- Oracle
- Teradata DB
- Netezza
- Mimer DB
- Microsoft SQL Server
- MySQL
- PostgreSQL
- many more...
Please submit bugs and patches. All contributors will be acknowledged. Thanks!
JayDeBeApi is released under the GNU Lesser General Public license
(LGPL). See the file COPYING
and COPYING.LESSER
in the
distribution for details.
- Next version - unreleased
- 1.2.3 - 2020-06-12
- Make pip install for Python 2 work by changing JPype1 requirement to older version
- Make pip install for Jython work by removing JPype1 requirement for Jython
- Removed cursor destructor to avoid issues with some JPype versions (please make sure you're always closing your cursors properly)
- 1.2.2 - 2020-06-04
- Return (big) decimal types as long value if scale is zero (thanks to @ministat)
- Fix DECIMAL and NUMERIC type conversion for Jython
- 1.2.1 - 2020-05-27
- Increased thread safety. Should resolve some of the No suitable driver found errors (thanks to @thealmightygrant)
- 1.2.0 - 2020-05-22
- Added compatibility to JPype1 0.7.2+ (thanks to @dpd)
- Support with statement (thanks to @Szczepanov)
- 1.1.2 - 2019-09-02
- Added compatibility to JPype1 0.7 (thanks to @Iverian, @Thrameos)
- Dropped python 2.6 support
- Fix build working with newer Maven versions
- Accidently force-pushed to master branch. Sorry for that.
- 1.1.1 - 2017-03-21
- Don't fail on dates before 1900 on Python < 3.
- 1.1.0 - 2017-03-19
- Support BIT and TINYINT type mappings (thanks @Mokubyow for reporting the issue).
- 1.0.0 - 2017-01-10
- Allow for db properties to be passed to the connect method. Probably incompatible to code based on previous versions. See documentation of the connect method. (Thanks @testlnord for you efforts and the patience.)
- New major version due to possible api incompatibility.
- 0.2.0 - 2015-04-26
- Python 3 support (requires JPype1 >= 0.6.0).
- 0.1.6 - 2015-04-10
- Fix Jython handling of Java exceptions that don't subclass python Exception
- Enrich exceptions with message from java SQLExceptions
- Be more specific about DB API exceptions: Distinguish DatabaseError and InterfaceError.
- Fix typo LONGNARCHAR vs LONGVARCHAR (thanks @datdo for reporting #4)
- 0.1.5 - 2015-03-02
- Add version number to module.
- Improve robustness of java to python type conversion.
- Support Time type.
- Add DB-API compliant exception handling.
- Minor documentation improvements.
- Some development related changes (Host project at github, use Travis CI, use JPype1 for tests).
- 0.1.4 - 2013-10-29
- More convenient way to setup Java classpath. Important note
check the changes to the
connect
method and adapt your code. - Honor
CLASSPATH
if used in JPype mode. - Set
.rowcount
properly. - Changed signature of
.setoutputsize()
to be DB-API compliant.
- More convenient way to setup Java classpath. Important note
check the changes to the
- 0.1.3 - 2011-01-27
- Fixed DB-API violation: Use
curs.execute('foo ?', (bar, baz))
instead ofcurs.execute('foo ?', bar, baz)
. - Free resources after
executemany
call. - Improved type handling. Initial support for BLOB columns.
- Fixed DB-API violation: Use
- 0.1.2 - 2011-01-25
-
easy_install JayDeBeApi
should really work.
-
- 0.1.1 - 2010-12-12
- Fixed bug #688290 "NULL values with converters error on fetch".
- Fixed bug #684909 "Selecting ROWIDs errors out on fetch".
- 0.1 - 2010-08-10
- Initial release.
- Extract Java calls to separate Java methods to increase performance.
- Check if https://code.launchpad.net/dbapi-compliance can help making JayDeBeApi more DB-API compliant.
- Test it on different databases and provide a flexible db specific pluign mechanism.
- SQLAlchemy modules (separate project)