How to export java class or java resource from Oracle database

If you need to export java class or java resource loaded to Oracle database with loadjava use this:

1) get fully qualified name of a class/resource:


SELECT DBMS_JAVA.longname (object_name), user_objects.*
  FROM SYS.user_objects
 WHERE object_type IN ('JAVA CLASS', 'JAVA RESOURCE')

2) use DBMS_JAVA.export_resource or DBMS_JAVA.export_resource accordingly. This example outputs first 4000 chars only but you get the idea once you have the BLOB:

DECLARE
   v_blob      BLOB;
   stringvar   VARCHAR2 (4000);
BEGIN
   DBMS_LOB.createtemporary (v_blob, TRUE, DBMS_LOB.SESSION);

   --dbms_java.export_class( 'com/mysource/MyClass', v_Blob ) ;

   DBMS_JAVA.export_resource ('resources/resource.xml', v_blob);
   stringvar := UTL_RAW.cast_to_varchar2 (DBMS_LOB.SUBSTR (v_blob, 4000, 1));
   DBMS_OUTPUT.put_line (stringvar);
END;

Execute DDL statement over dynamic DB link

If you want to execute DDL statement <sql_statement> over DB link <db_link_name> try using this:


  DECLARE
    t_cursor PLS_INTEGER;
  BEGIN
    t_cursor := dbms_sql.open_cursor'||db_link_name||';
    dbms_sql.parse'||db_link_name||'(t_cursor, '''||sql_statement||''', dbms_sql.NATIVE);
    dbms_sql.close_cursor'||db_link_name||'(t_cursor);
  END;

This solution is quite tricky and I guess this wouldn't work for every DDL statement but it worked for me in 10g for enabling/disabling constraints and indexes. Another good thing about it is that DBlink name is dynamic and not hard-coded.

Search for a string in files in SunOS

The problem seems to be very easy to google for but many options for grep I was able to find didn't work for me. So if you want to get a list of file names containing some specific string in SunOS or Solaris you can use this command:

find . -type f | xargs grep -l "<string to search>"

use this if you want to ignore access/file read errors:

find . -type f 2>/dev/null | xargs grep -l "<string to search>"  2>/dev/null

oracle loadjava error: Unexpected Signal : EXCEPTION_ACCESS_VIOLATION (0xc0000005) occurred at PC=0x8077E76

After installing latest updates for Windows 7 64-bit recently, I've found out Oracle's loadjava is now giving me this error:



Unexpected Signal : EXCEPTION_ACCESS_VIOLATION (0xc0000005) occurred at PC=0x8077E76
Function=[Unknown.]
Library=C:\oracle\product\10.2.0\client_1\jdk\jre\bin\client\jvm.dll

...

Current Java thread:
at oracle.jdbc.driver.T2CConnection.t2cCreateState(Native Method)
at oracle.jdbc.driver.T2CConnection.logon(T2CConnection.java:346)
at oracle.jdbc.driver.PhysicalConnection.<init>(PhysicalConnection.java:413)
at oracle.jdbc.driver.T2CConnection.<init>(T2CConnection.java:131)
at oracle.jdbc.driver.T2CDriverExtension.getConnection(T2CDriverExtension.java:77)
at oracle.jdbc.driver.OracleDriver.connect(OracleDriver.java:752)
at java.sql.DriverManager.getConnection(DriverManager.java:512)
- locked <0x141ae388> (a java.lang.Class)
at java.sql.DriverManager.getConnection(DriverManager.java:140)
- locked <0x141ae388> (a java.lang.Class)
at oracle.aurora.server.tools.loadjava.DatabaseOptions.getConnection(DatabaseOptions.java:180)
at oracle.aurora.server.tools.loadjava.DatabaseOptions.connect(DatabaseOptions.java:123)
at oracle.aurora.server.tools.loadjava.LoadJavaState.getConnection(LoadJavaState.java:409)
at oracle.aurora.server.tools.loadjava.LoadJavaState.getOldMD5(LoadJavaState.java:696)
at oracle.aurora.server.tools.loadjava.ClientSchemaObject.getOldMD5(ClientSchemaObject.java:52)
at oracle.aurora.server.tools.loadjava.SchemaObject.doCreate(SchemaObject.java:172)
at oracle.aurora.server.tools.loadjava.SchemaObject.process1(SchemaObject.java:215)
at oracle.aurora.server.tools.loadjava.LoadJava.add(LoadJava.java:532)
at oracle.aurora.server.tools.loadjava.LoadJava.addObject(LoadJava.java:513)
at oracle.aurora.server.tools.loadjava.LoadJava.add(LoadJava.java:451)
at oracle.aurora.server.tools.loadjava.LoadJava.add(LoadJava.java:380)
at oracle.aurora.server.tools.loadjava.LoadJava.addJar(LoadJava.java:727)
at oracle.aurora.server.tools.loadjava.LoadJava.add(LoadJava.java:432)
at oracle.aurora.server.tools.loadjava.LoadJava.add(LoadJava.java:380)
at oracle.aurora.server.tools.loadjava.LoadJava.add(LoadJava.java:349)
at oracle.aurora.server.tools.loadjava.LoadJava.add(LoadJava.java:652)
at oracle.aurora.server.tools.loadjava.LoadJava.processDeferredFiles(LoadJava.java:617)
at oracle.aurora.server.tools.loadjava.LoadJava.process(LoadJava.java:818)
at oracle.aurora.server.tools.loadjava.LoadJava.command(LoadJava.java:251)
at oracle.aurora.server.tools.loadjava.LoadJavaMain.run(LoadJavaMain.java:103)
at oracle.aurora.server.tools.loadjava.LoadJavaMain.main(LoadJavaMain.java:28)

Dynamic libraries:
0x00400000 - 0x0040B000 C:\oracle\product\10.2.0\client_1\jdk\jre\bin\java.exe
0x77C80000 - 0x77E00000 C:\Windows\SysWOW64\ntdll.dll
...

Heap at VM Abort:
Heap
 def new generation   total 576K, used 391K [0x10010000, 0x100b0000, 0x104f0000)
...

#
# HotSpot Virtual Machine Error : EXCEPTION_ACCESS_VIOLATION
# Error ID : 4F530E43505002EF
# Please report this error at
# http://java.sun.com/cgi-bin/bugreport.cgi
#
# Java VM: Java HotSpot(TM) Client VM (1.4.2_08-b03 interpreted mode)
#

As the solution to this problem I found to be installing Oracle 11g (v. 11.1.0) client instead of existing 10g (v. 10.2.0) one, specifically win32_11gR1_client. Funnily enough, I wasn't even able to quickly find the client distributive on Oracle website so here's the link for you: http://www.oracle.com/technetwork/database/enterprise-edition/downloads/112010-win32soft-098987.html