• Hosted Lotus Connections 3
• Hosted VDI – IBM Smart Business Server 2
• Hosted Domino Mail, Collaboration, and Knowledge Management 8.5.1
• Hosted DB2 9.7

As a follow up to the DB2 Discovery Kit post, here is a link the the Updated IBM DB2 e-kit for Database Professionals

This new kit has a number of resources for migrating to DB2 from other databases, such as Oracle.

From the thread “My Quest for Understanding Business Intelligence” this comment was posted by Leslie Dudley:

Business Intelligence Background

A little off topic perhaps, but as an IT business intelligence worker who was interviewing during the economic downturn, I have a slightly different perspective. First, I found myself to be fortunate to be in one of the few growth fields. One of the reasons that the large consulting firms have been investing and focusing on the Business Intelligence field is because it was the first area to show growth activity during the most recent recession.

Business Intelligence and Technology

My other slightly off topic point is that the resurgence of interest in Business Intelligence technology is not a fad but the inevitable result of the major shift in media consumption in our culture. In BI IT we are the beneficiaries of the change in how our society consumes media. As a result of both a cultural shift and the recession, media spend moved from traditional to digital. The effect has been the rapidly growing influx of big data that makes it possible to measure the impact of the new media marketing – digital advertising, email, search, social media, site metrics, engagement.

Business Intelligence and Culture

The cultural shift has changed the context of business intelligence. No longer can spreadsheets and MS Access databases meet the needs of the business to identify actionable insights from data. The challenge of handling the pedabytes of data being generated by multiple sources is one that IT data warehousing workers are uniquely qualified to handle. The growth of business intelligence is not a fad, nor a recognition of IT, it is the ripple effect of the disruptive innovation going in technology, digital media and culture at large.

Business Intelligence in Context

I do agree that business intelligence is a business process. And I do agree that technology workers are being called on to meet the challenges of BI. But I don’t see a ‘BI Movement’. I see a broad cultural shift in the way we consume data and media.

Technologists with experience in handling and making sense of big data are rising to the challenge, and many others are trying to get on board a growth industry. Yes, many people want to learn more about the technology for managing and analyzing big data from disparate sources. It is at this point in time a growth field.

But the impetus is not BI technology: the movement changing the face and players in BI is not BI technology. We are downstream from more significant cultural shifts being played out by the success of disruptive innovations – google, search analytics, site analytics, ad-serving, social media, entertainment and news delivery. To get an idea of where our industry is heading look forward – to the semantic web.

Our role as workers with knowledge of handling and analyzing disparate, big data will grow and the opportunities will be in understanding semantic data, unstructured data and relationships. Marketing is moving ahead quickly now due to being nimble, fast and flush. Academia is lumbering forward with complex concepts, ontologies and methodologies. We are feeling the early rumblings of what will happen when the two begin intersecting.

Posted on LinkedIn by Leslie Dudley, member of the Business Intelligence Professionals group. More articles on Business Intelligence…

Writing efficient SQL SELECTqueries for DB2 can be tricky. Some general SQL guidelines apply, and there are also specific practices that apply only to DB2.

Solution

Here is a list of tips you can use to write good SELECT queries:

• Avoid SELECT * in your queries. Instead, state the columns you want to select.
• Use the consistent acronyms to alias your table names (makes it easier to read joins)
• Use FETCH ONLY x ROWS to limit the results set
• Use CASE or MERGE instead of UNION ALL

References

• Efficient SELECT statements
• Writing and Tuning Queries for Optimal Performance

One of the great features of DB2 is that it can be extended with custom code using SQL, C/C++, Java and COBOL. One of the great new features added to DB2 in 9.7 is the ability to run native Oracle PL/SQL code, that capability opens up a world of possibilities, and at the same time, the need to extend DB2 with functions that might have been available on the Oracle install and now need to be replicated on DB2. In this short article I describe how to extend DB2 9.7 with Java UDFs.

Prerequisites

• Check that Java is properly installed and configured on DB2:
db2 get dbm config|grep JDK
  The output should show the path to the JDK installation in DB2. If that isn’t the case, you need to consult the DB2 install manual and make sure Java is installed and configured for DB2.
• Make sure that your user has access to java and javac, and that it is the same version or compatible with DB2′s JDK
• Set the database manager parameter KEEPFENCED to NO, so that the UDF will be reloaded in each call.

Writing the test code

• Use your favorite text editor or IDE and create a file called udftest.java with the sample code:

  public class udftest {
          public static String udftest(String domainName) {
                  return "Domain Name: " + domainName;
          }
  }

• Compile the java program:
javac udftest.java
• Create a jar file:
jar cvf udftest.jar udftest.class
• Register the jar file with DB2:
db2 "CALL sqlj.install_jar('file:/home/bnagy/dev/java/udf/udftest.jar','UDFTESTJAR')"

Creating the UDF in DB2

• Use your favorite text editor or IDE and create a file called udftest-create.sql with the sample code:
CONNECT TO SAMPLE;
CREATE FUNCTION udftest(VARCHAR(255)) RETURNS VARCHAR(255)
FENCED
EXTERNAL NAME 'UDFTESTJAR:udftest.udftest'
NOT VARIANT NO SQL PARAMETER STYLE java LANGUAGE java
NO EXTERNAL ACTION;
CONNECT RESET;
• Run the scritpt in DB2:
db2 -tvf udftest-create.sql

Testing

To check that the function works, run the following command on the command line:
db2 "select udftest('test.com') from sysibm.sysdummy1"
You should get a regular SELECT result set with the expected values. If something goes wrong, you can look at the db2diag.log that will contain any Java stack trace that would be generated.

References

• Up and Running With DB2 for Linux (Ibm Redbooks.)

Best method from Dan Lyke: Apache::DBI will pool across Perl programs, and you don’t have to change anything in your scripts.

Next best method from Gilles DAROLD: in your perl script use the following code

use vars qw($dbh);

$dbh ||= DBI::connect($datasrc, $dbuser, $dbpwd);

These can be use to create a database connection class in Perl that can handle transparently the connection / reconnection and disconnection for your code. The end use code doesn’t have to be OO, thus the connection object can be reused in any legacy code.

CREATE TABLE temp AS SELECT DISTINCT ON (email) * FROM table_to_deduplicate;
DROP TABLE table_to_deduplicate;
ALTER TABLE temp RENAME TO table_to_deduplicate;

Be mindful of the fact that this process will not preserve the constraints on the original table. So if you have indexes, NOT NULL attributes, primary keys, foreign keys, you’ll have to recreate them.

CREATE TABLE temp AS SELECT DISTINCT * FROM table_to_deduplicate;
DROP TABLE table_to_deduplicate;
ALTER TABLE temp RENAME TO table_to_deduplicate;

Be mindful of the fact that this process will not preserve the constraints on the original table. So if you have indexes, NOT NULL attributes, primary keys, foreign keys, you’ll have to recreate them.

• Get download link from http://www-306.ibm.com/software/data/db2/9/download.html
• Run the following commands:

  wget <use link retrieved above>
  tar xvzf v9.5_linuxx64_client.tar.gz
  client/db2_install (accept defaults)
  groupadd -g 999 db2iadm1
  groupadd -g 998 db2fadm1
  groupadd -g 997 dasadm1
  useradd -u 1004 -g db2iadm1 -m -d /home/db2inst1 db2inst1
  useradd -u 1003 -g db2fadm1 -m -d /home/db2fenc1 db2fenc1
  useradd -u 1002 -g dasadm1 -m -d /home/dasusr1 dasusr1
  /opt/ibm/db2/V9.5/instance/db2icrt -a server -u db2fenc1 db2inst1
  cp /home/db2inst1/sqllib/db2profile /etc/profile.d/db2profile.sh

• If you run into errors during the install process such as:

  /root/client/db2/linuxamd64/install/db2_install: line 277: /root/tmp/db2_install.15043.rsp: Not a directory
  /root/client/db2/linuxamd64/install/db2_install: line 285: /root/tmp/db2_install.15043.rsp: Not a directory
  /root/client/db2/linuxamd64/install/db2setup: /tmp/db2.tmp.15043/db2/linuxamd64/install//db2chgpath: /bin/sh: bad interpreter: Permission denied
  /root/client/db2/linuxamd64/install/db2setup: /tmp/db2.tmp.15043/db2/linuxamd64/install//db2setup_exec: /bin/sh: bad interpreter: Permission denied

  Because /tmp is mounted with the noexec option the db2_install fails. It looks like it prefers to copy all the files to tmp then install (not a secure method).

  Open up the platform specific db2_install file (noted above in the errors)

  db2/linuxamd64/install/db2_install

  Edit the TMPDIR line:

  TMPDIR=${DB2TMPDIR:-/tmp}

  to something like

  TMPDIR=${DB2TMPDIR:-/root/tmp}

  (*directory must exist or be created!)

  Next, make sure DB2TMPDIR is a valid environment variable matching above:

   [root@server ~/] export DB2TMPDIR=~/tmp

  Then start the db2_install from the top level directory, IE

   ./db2_install

• there is one more step: adding the catalog entry to for the remote database which consists of two steps

• create the instance alias using the following commands:

      db2 "catalog tcpip node remoteinst remote remotehost server 50000"
      db2 "terminate"
  

• create the database alias using the following commands:

      db2 "catalog database testdb as remotedb at node remoteinst authentication server"
      db2 "terminate"
  

References:

• Getting Started With IBM DB2