IBM MAINFRAME HELP & SUPPORT FORUMS

nagalakshmi · Joined: 23 Feb 2005 Posts: 7

Hi,

Please Clarify questions being asked for interview :

1. How many nested Queries at maximum can a Select statement can have?

2. How many Maximum no. of columns can a DB2 table can have?

Thanks
Lakshmi

mcmillan · Joined: 18 May 2003 Posts: 923 Location: India

Hi,

Please check this link:

http://ibmmainframes.com/references.php

Click on: DB2-SQL PROGRAMMING LIMITS under References: DataBases
section.

khannay2k · Joined: 24 Feb 2005 Posts: 26 Location: Bangalore

Hi Nagalakshmi,

1. How many nested Queries at maximum can a Select statement can have?

At the max you can have 15 nested queries, and total of 16 queries in a select statment.

2. How many Maximum no. of columns can a DB2 table can have?

For this i have mentioned that u can have at the max 224 columns during the earlier posts. go through the posts, and see that you are not repeating the queries.

Khanna.

Rajshekhar V Patil · Joined: 23 Feb 2005 Posts: 7 Location: Mumbai

2. How many Maximum no. of columns can a DB2 table can have?
A.

Maximum no. of columns can a DB2 table is 750.

When VSAM to DB2 conversion that time max. is 255(migrating the file into DB2 tables)

pradeepsamson · Joined: 08 Mar 2005 Posts: 5 Location: Pune

Hi,

1) In JCL sort card sum fields = none for eliminating duplicates. How can I retrieve only duplicates?
2) How will you make sure that your SELECT query retrieves only one row always?
3) DISTINCT is used for eliminating duplicate rows in DB2. How can retrieve all the duplicates (A sample query is highly appreciated)?
4) I have a sort requirement like 5 records. In that 4 are same and 1 is different. I want to get only that 1 record. How? Anyone have an idea about "EQUALS" in sort card?
5) What would be your first approach after getting -805?
6) How can I know my particular program is using particular "PLAN"?
8)I have written program, ?PROGRAM-ID. ADD. Saved this particular program in a PDS as member name TEST. Will it work or throw any error?
9) I am compiling a COBOL db2 program suddenly my Db2 brought down what will happen?
10) What is Z-OS?

Cheers!
Pradeep Samson.

harish_mf · Joined: 31 Jul 2005 Posts: 21 Location: bangalore

pradeepsamson wrote: Hi,

1) In JCL sort card sum fields = none for eliminating duplicates. How can I retrieve only duplicates?
2) How will you make sure that your SELECT query retrieves only one row always?
3) DISTINCT is used for eliminating duplicate rows in DB2. How can retrieve all the duplicates (A sample query is highly appreciated)?
4) I have a sort requirement like 5 records. In that 4 are same and 1 is different. I want to get only that 1 record. How? Anyone have an idea about "EQUALS" in sort card?
5) What would be your first approach after getting -805?
6) How can I know my particular program is using particular "PLAN"?
8)I have written program, ?PROGRAM-ID. ADD. Saved this particular program in a PDS as member name TEST. Will it work or throw any error?
9) I am compiling a COBOL db2 program suddenly my Db2 brought down what will happen?
10) What is Z-OS?

Cheers!
Pradeep Samson.

harish_mf · Joined: 31 Jul 2005 Posts: 21 Location: bangalore

harish_mf wrote: pradeepsamson wrote: Hi,

1) In JCL sort card sum fields = none for eliminating duplicates. How can I retrieve only duplicates?
:- sum fields=none, xsum
2) How will you make sure that your SELECT query retrieves only one row always?
:- by if not it will give -811(when cursor is not declared).

3) DISTINCT is used for eliminating duplicate rows in DB2. How can retrieve all the duplicates (A sample query is highly appreciated)?
:-n use Where Exits and Count(*)
4) I have a sort requirement like 5 records. In that 4 are same and 1 is different. I want to get only that 1 record. How? Anyone have an idea about "EQUALS" in sort card?
:- Thia I have to try.
5) What would be your first approach after getting -805?
:- Rebinding is widely used.
6) How can I know my particular program is using particular "PLAN"?
:- Plan is selected through its indexes.
8)I have written program, ?PROGRAM-ID. ADD. Saved this particular program in a PDS as member name TEST. Will it work or throw any error?

:- It will work.
9) I am compiling a COBOL db2 program suddenly my Db2 brought down what will happen?
:-For pre compiling no matter Db2 is up r down.
10) What is Z-OS?
:Zseries os , advanced with release 13 and 14.

Cheers!
Pradeep Samson.

parikshit123 · Joined: 01 Jul 2005 Posts: 279 Location: India

Hi pradeepsamson and harish_mf,

can you guys please avoid cramming a lots of irrelevent questions from the post?

if you wish, you guys can open a new topic after searching the forum.

saravanant · Joined: 06 Sep 2006 Posts: 6 Location: chennai

nagalakshmi wrote: Hi,

Please Clarify questions being asked for interview :

1. How many nested Queries at maximum can a Select statement can have?

2. How many Maximum no. of columns can a DB2 table can have?

Max no.of columns in a table is 242

Thanks
Lakshmi