I'm trying to do some testing on our JDBC driver using Python.
Initially figuring out JPype, I eventually managed to connect the driver and execute select queries like so (reproducing a generalized snippet):
from __future__ import print_function
from jpype import *
#Start JVM, attach the driver jar
jvmpath = 'path/to/libjvm.so'
classpath = 'path/to/JDBC_Driver.jar'
startJVM(jvmpath, '-ea', '-Djava.class.path=' + classpath)
# Magic line 1
driver = JPackage('sql').Our_Driver
# Initiating a connection via DriverManager()
jdbc_uri = 'jdbc:our_database://localhost:port/database','user', 'passwd')
conn = java.sql.DriverManager.getConnection(jdbc_uri)
# Executing a statement
stmt = conn.createStatement()
rs = stmt.executeQuery ('select top 10 * from some_table')
# Extracting results
while rs.next():
''' Magic #2 - rs.getStuff() only works inside a while loop '''
print (rs.getString('col_name'))
However, I've failed to to batch inserts, which is what I wanted to test. Even when executeBatch()
returned a jpype int[], which should indicate a successful insert, the table was not updated.
I then decided to try out py4j.
My plight - I'm having a hard time figuring out how to do the same thing as above. It is said py4j does not start a JVM on its own, and that the Java code needs to be prearranged with a GatewayServer(), so I'm not sure it's even feasible.
On the other hand, there's a library named py4jdbc that does just that.
I tinkered through the dbapi.py code but didn't quite understand the flow, and am pretty much jammed.
If anyone understands how to load a JDBC driver from a .jar file with py4j and can point me in the right direction, I'd be much grateful.
add a commit after adding the records and before retrieving.
conn.commit()