The IBM DB2 Enterprise Server Edition is a relational model database server developed by IBM. It primarily runs on Unix (namely AIX), Linux, IBM i (formerly OS/400), z/OS and Windows servers.

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Table orders regarding Nested loop join in DB2

First I would like to cite the existing post Table order in Join Query so the author is saying that the table order really doesn't make things(result, access plan)different. I have doubt on this ...
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410 views

Can I optimize for the zIIP processor?

Is it possible to change SQL in a z/OS mainframe COBOL application so that it becomes eligible to be directed to the IBM System z Integrated Information Processor (zIIP)?
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eliminate extra spaces in VARCHAR columns

In a table, I have an ID column defined as BIGINT(8) and one VOUCHER column that is VARCHAR(100). No matter the actual length of the value in that field, the SQL always returns a full length value, ...
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1answer
782 views

DB2 equivalent to T-SQL's REPLICATE?

In T-SQL there is a method, REPLICATE(char,N), which will make a string with N values of a certain character. This is very helpful when querying into JDE. Does anyone know if there is a DB2 ...
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1answer
2k views

Filtering on a virtual column from a UNION ALL with LEFT OUTER join causes a table scan?

I asked this question on SO but havn't got many bites and even a vote to close for being "Off Topic." So, I thought this stack exchange might be better suited. Consider the following SQL... SELECT ...
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2answers
622 views

What is the recommended Buffer Pool size on a 2GB RAM PC?

I installed DB2 Express-C on a PC with 2 GB RAM and running Windows Server 2008 R2 OS. While creating a new database, there is an option to set Buffer Pool size with default set to 4K. How much is ...
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3answers
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What is the purpose of having a table NOT LOGGED INITIALLY

I came across this recently. When defining a table in DB2 LUW (at least 9.5 or higher), you can define it as NOT LOGGED INITIALLY. Example from the book I read: CREATE TABLE products ( productID ...
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1answer
26k views

How do I grant all privileges to local db2admin with DB2 9.7 on Windows?

I have as my developer station a laptop with OS Windows XP Professional Edition, Service Pack 3. I have downloaded and installed IBM DB2 UDB 9.7 fix pack 4, of the Express-C edition. I have a local ...
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1answer
1k views

How do I resolve this data source connection issue with Cognos?

We have (fairly recently) installed IBM's Cognos 10 as our business intelligence reporting tool. Most of the databases that we report over are DB2 9.7 LUW Enterprise Edition. We installed the DB2 ...
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2answers
793 views

Syntax changes between DB2 for i (DB2/400) v5r4 and v6r1

Does anyone know where can I find list of syntax changes between DB2 for i v5r4 and v6r1? We are currently migrating a backing database for an application from DB2 for i v5r4 to v6r1 and found out ...
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1answer
309 views

What is object Server?

As I was reading article I came across IBM's site about object Server. What actually is Object Server and what are it's uses? Can this be explained for a beginner?
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1answer
318 views

Important distinctions between DBMSs [closed]

DBA is a career I'm strongly considering after school, but my limited experience mostly involves some PL/SQL Oracle web programming, some basic PHP/MySQL web pages, and some queries in SQL Server. ...
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1answer
479 views

Can High Water Mark be cleared?

Lately I experience below errors when restoring db2 database SQL2043N Unable to start a child process or thread SQL1084C Shared memory segments cannot be allocated db2stop and then db2start ...
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1answer
2k views

DROP SCHEMA in db2

How do I drop a schema in db2 if it has got some objects in it? db2 DROP SCHEMA SCHEMA_NAME For some reason I am not able to drop the tables in the schema, so how can I force to drop the ...
5
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1answer
185 views

Will I need more system resources to run DB2 instead of MySQL?

I need to convert my web application from MySQL to run on DB2. I need to know in advance whether I will need a high spec server to ensure the web application performs at the same speed as it does now ...
4
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1answer
923 views

How to UPDATE just one record in DB2?

In DB2, I need to do a SELECT FROM UPDATE, to put an update + select in a single transaction. But I need to make sure to update only one record per transaction. Familiar with the LIMIT clause from ...
3
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1answer
2k views

DB2 9.5 How to get tablespace monitor information?

How can I get information about tablespace in DB2 9.5? I need to review information about if the autoresize option is enabled or disabled.
3
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1answer
616 views

Help with DB2 Procedure

I have the following query: CREATE PROCEDURE MYPROC( IN @TABLES VARCHAR(500)) DYNAMIC RESULT SETS 1 LANGUAGE SQL SPECIFIC MYPROC NOT DETERMINISTIC MODIFIES SQL DATA CALLED ON NULL INPUT BEGIN ...
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1answer
232 views

can i backup multiple db2 databases at the same time?

in db2 9.5 LUW i have one db instance to which i just added a second database. we don't have TSM or multiple partitions which is what all the documentation seems to be about when i search the web for ...
5
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1answer
3k views

BLOB on DB2 v9 on z/OS

What are cons and pros of using BLOBs on DB2 v9 (or later) on z/OS? Clarification: are there some limits (like influence on reorg, HA)? We would like to store large amount of files: 10 millions in ...
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2answers
1k views

altering a db2 table with huge amount of data

I have a table in DB2 which is having 99 columns and 900,000 records of data. I want to alter the table with one extra column as below: ALTER TABLE MYSCHEMA.PRODUCT ADD UPDATE_DT DATE However, the ...
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1answer
1k views

DB2: database hangs while trying to execute simple select query on specific table

No errors or warnings, database just hangs while trying to execute simple select query on specific table. Other tables are accessible until I trying to query specific (faulty) table. This should not ...
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2answers
600 views

Generalisation in databases

I am working on a Hospital Management project in DB2. I have one table for staff with a primary key of staff_id. The hospital has to have different staff... e.g doctors,nurses,e.t.c. Is it better to ...
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3answers
719 views

Single versus Multiple databases

I am working on a hospital management system using DB2 with pureXML. Is better to use a single database for all the data (patient, doctor details, appointments, history, medicines, etc) or to use ...
2
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1answer
2k views

Migration from DB2 to MySQL

Does any one have experience on migration from DB2 to MySQL ? Please share with me. I tried googling, but I have not received much information on this.
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1answer
295 views

In DB2, what are the alternative ways of evaluating an index's (or several indexes) benefit?

I'm trying to evaluate different approaches to analyzing the benefit of changing the set of indexes that are available. If I pick some representative queries from my workload, I can run EXPLAIN and ...
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1answer
238 views

How do you convert IBM DB2's recursive increment to MySQL version?

DB2 Queries: WITH TABLE1 (YEAR_END) as( VALUES (2011)) , TABLE2 (YEAR_END) AS ( VALUES(2011)) , TABLE3 (YEARS) AS ( SELECT 0+2008 FROM TABLE1 T1, TABLE2 T2 union ...
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1answer
78 views

Can you control what tags are used in an XML column?

We allow our developers to use XML columns to store data. We want to provide standard names to XML tags. As a DBA, can we prevent the users from adding XML tags that are not predefined?
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2answers
2k views

DB2 Trigger: only update current row

I've created following trigger : CREATE TRIGGER probeer2 AFTER INSERT ON libtn01leb.kofax_release FOR EACH ROW UPDATE libtn01leb.kofax_release SET RRNR='bleh' This trigger will update EVERY ...
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1answer
490 views

What are the best practices for ETL of data from one OLTP system to another, Part 2?

Ok, I originally started a question a ways back called "What are the best practices for ETL of data from one OLTP system to another?". And as you can probably tell from most of my questions so far, ...
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1answer
798 views

What are the best practices for ETL of data from one OLTP system to another?

First off, I want to post that I am a developer and not a DBA, so I am trying to approach this from the standpoint of what is the best thing to do, rather than just assuming I can do everything ...
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1answer
1k views

What does TBSCAN GENROW mean in Explain Plan?

In a DB2 Explain Plan, what does TBSCAN GENROW (line 5 below) mean? SELECT STATEMENT ( Estimated Costs = 1.811E+03 [timerons] ) 1 RETURN 2 NLJOIN 3 [O] TBSCAN 4 SORT ...
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2answers
463 views

What is the best practice for mapping from natural keys to integer-based keys? (ETL)

This question originates more from an "enterprise architecture" point of view. (Reason being, our company is just starting to get into data management, and actually having DBA's -- I know, horrific ...
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0answers
69 views

If anyone has experience about bugs ,problems or any related link of DB2 v.10 FOR ZOS , please reply? [closed]

Hi I want to use db2 10 for zos. If anyone has experience about bugs ,problems or any related link of DB2 v.10, please reply? thanks for your attention.
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1answer
462 views

What does HSJOIN mean in an Explain Plan?

I have the following EXPLAIN PLAN results from a query on my DB2 database. 0 SELECT STATEMENT ( Estimated Costs = 5.928E+02 [timerons] ) 1 RETURN 2 HSJOIN 3 [O] ...