Using JPype - How can I access JDBC Meta Data Functions
-
21-12-2019 - |
Question
I'm using JayDeBeAPI which uses JPype to load FileMaker's JDBC driver and pull data.
But I also want to be able to get a listing of all tables in the database.
In the JDBC documentation (page 55) it lists the following functions:
The JDBC client driver supports the following Meta Data functions:
getColumns
getColumnPrivileges
getMetaData
getTypeInfo
getTables
getTableTypes
Any ideas how I might call them from JPype or JayDeBeAPI?
If it helps, here's my current code:
import jaydebeapi
import jpype
jar = r'/opt/drivers/fmjdbc.jar'
args='-Djava.class.path=%s' % jar
jvm_path = jpype.getDefaultJVMPath()
jpype.startJVM(jvm_path, args)
conn = jaydebeapi.connect('com.filemaker.jdbc.Driver',
SETTINGS['SOURCE_URL'], SETTINGS['SOURCE_UID'], SETTINGS['SOURCE_PW'])
curs = conn.cursor()
#Sample Query:
curs.execute("select * from table")
result_rows = curs.fetchall()
Update:
Here's some progress and it seems like it should work, but I'm getting the error below. Any ideas?
> conn.jconn.metadata.getTables()
*** RuntimeError: No matching overloads found. at src/native/common/jp_method.cpp:121
Solution
Ok, thanks to eltabo and Juan Mellado I figured it out!
I just had to pass in the correct parameters to match the method signature.
Here's the working code:
import jaydebeapi
import jpype
jar = r'/opt/drivers/fmjdbc.jar'
args='-Djava.class.path=%s' % jar
jvm_path = jpype.getDefaultJVMPath()
jpype.startJVM(jvm_path, args)
conn = jaydebeapi.connect('com.filemaker.jdbc.Driver',
SETTINGS['SOURCE_URL'], SETTINGS['SOURCE_UID'], SETTINGS['SOURCE_PW'])
results = source_conn.jconn.getMetaData().getTables(None, None, "%", None)
#I'm not sure if this is how to read the result set, but jaydebeapi's cursor object
# has a lot of logic for getting information out of a result set, so let's harness
# that.
table_reader_cursor = source_conn.cursor()
table_reader_cursor._rs = results
read_results = table_reader_cursor.fetchall()
#get just the table names
[row[2] for row in read_results if row[3]=='TABLE']
OTHER TIPS
From ResultSet Javadoc:
public ResultSet getTables(String catalog,
String schemaPattern,
String tableNamePattern,
String[] types)
throws SQLException
You need pass the four parameter to the method. I'm not a python developer, but in Java I use :
ResultSet rs = metadata.getTables(null, "public", "%" ,new String[] {"TABLE"} );
to get all the tables (and only the tables) in a schema.
Regards.