how the cobol program look like when we r using ksds?

babun · New User Joined: 03 Aug 2005 Posts: 9 Location: bangalore

how the cobol program look alike when we r using Vsam ksds? what r all the necessary action on cobol pgm?

babun · New User Joined: 03 Aug 2005 Posts: 9 Location: bangalore

can we use SELECT * FROM ------; query in Embedded SQL? if we can why ? if we can't why?
pls let me know folks?

thanooz · Active User Joined: 28 Jun 2005 Posts: 105

hi
babum

when you are using ksds

the main consideration on

file control

select filename assign to jcldd
organiztion is indexed
access mode sequential/random/dynamic
record key is file-key-field
alternate key is file-alternate-key field.

if it is sequential access no bother of record key and alternate key.

thanks,
thanooz.

thanooz · Active User Joined: 28 Jun 2005 Posts: 105

hi babu

we cont in embeded sql. because it gives error.

Ravi Gopal · New User Joined: 04 Aug 2005 Posts: 3

Hi Babun,

The reason for not using SELECT * FROM query in the program is:

1.If the table structure is changed (a field is added), the program will have to be modified.

2.Program might retrieve the columns which it might not use, leading on I/O over head.

Cheers
Ravi

babun · New User Joined: 03 Aug 2005 Posts: 9 Location: bangalore

Thanks ravi
thank you for your answer..
it's clear

thanooz · Active User Joined: 28 Jun 2005 Posts: 105

hi babu

For three reasons:
If the table structure is changed (a field is added), the program will have to be modified
Program might retrieve the columns which it might not use, leading on I/O over head.
The chance of an index only scan is lost.

thanks,
thanooz.