Mainframe, MVS and zOS Discussion

Hi All,

Does any one have M204 database document ? Please advise about this.

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Why not download and install the free DB2 system for Windows onto your personal machine?


Or even download any old RDBMS that uses SQL and experiment with that. For the record I use SQLite and it gets me through all I need to know with standard SQL queries.


Thanks for the suggestion I did not ...

Thanks enrico and Robert.

I'm in to support project for some time where SPUFI and QMF use is restricted.

Thanks, tried it and got the result that column names should be identified and not necessarily be part of the select.

Quoting from manual

Column names in sort keys: A column name in a sort-key must conform to the following rules:

If the column name is qualified, the query must be a subselect. The column name must unambiguously identify a column of a table, view, or nested table expression in the FROM clause ...

Thanks Chandan. But I am not allowed to create some test data to test these things. With out test tables how can I do it?

This is not as true as it used to be. When a 3390 was a physical box, then yes CI and CA splits could cause issues since they would alter the sequence of sequential reads by causing a jump to a different cylinder then a jump back. These days with emulated 3390 disk drive, I'm not sure that concern ...

Pandora-Box wrote:Check the below diagram , I have tried to explain join in very quick way hope this is clear

JOINS.jpg

Thanks a lot for the diagram Pandora-Box.

How can we practice more of mainframes, like any windows's language?

Hi,

To a certain level I understand that VSAM data sets can undergo CI and CA splits as they are updated and records are added or inserted. I have been told that this is not always a bad thing, however sometimes for some data set it can cause excessive processing and I/O. How do we identify such ...

How do you get time for creating a website apart from your daily job??

Hi,

I also use google.

I use computers for 7 to 8 hours in office and 1-2 hours at home.

168

Hi,

Instead of getting them in SPOOL, can we copy the JESMSGLG to a dataset? Can I also copy JESYSMSG in to a dataset? Will this require a special MSGCLASS to do it automatically. If it was a SYSOUT=*, I could have coded SYSOUT=dataset name but what to do for JESMSGLG and JESYSMSG.

Hi,

The concepts of joins are very confusing for me. I really do not undertand the difference between Inner Join and Outer Joins. I have been looking for some good example on inner join, left outer join, and right outer join but could not find something for mainframes.

Could someone provide me ...

Hi,

In "Order By" Clause in DB2, does the clause require the columns to be selected using select statement on which order is to be performed? If it is not then how DB2 knows about those columns?

155

Hi,

What is the maximum decimal position a numeric data item can have in COBOL. When I search for it I got the details about ARTH(EXTEND) but that's about using 31 digits in a numeric number. So does that mean if I want to use a decimal number, it can have 31-digits after decimal with that option ...