Still celebrating National IT Professionals Day with 3 months of free Premium Membership. Use Code ITDAY17

x
?
Solved

finding which fields are "nullable"

Posted on 2013-07-01
4
Medium Priority
?
880 Views
Last Modified: 2013-07-01
hi

i'm looking for a piece of sql that will enable me to see which fields in a table can have null values.

i've tried select * from syscolumns where id=(select id FROM sysobjects where name='table_name') but this doesn't give that attribute.

i'm calling this sql from VBA, so i cannot use sp_help as the "nextrecordset" method doesn't work when using sybase

any ideas?
0
Comment
Question by:Neilgordo
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
4 Comments
 
LVL 23

Accepted Solution

by:
Steve Wales earned 600 total points
ID: 39291209
Sybase documentation on the syscolumns table says that bit 3 of the status column us used to define if a column is nullable or not:

http://infocenter.sybase.com/help/index.jsp?topic=/com.sybase.infocenter.dc36274.1570/html/tables/X14340.htm

Searching a little more from there I found this:

http://database.ittoolbox.com/groups/technical-functional/sybase-l/sql-server-isnullable-equivalent-in-sybase-404087

With this code snippet:

select o.name as tableanme, c.name as columnname, convert(bit, (status & 8)) as nulls
from syscolumns c
join sysobjects o
on c.id = o.id
where o.type = 'U'
order by o.name, c.name

Open in new window


Give that a shot and see if it works for you.
0
 
LVL 27

Expert Comment

by:wilcoxon
ID: 39291293
sjwales answer will only work in a recent(ish) version of Sybase.  Iirc, bit type was added in ASE 15.  If you have an earlier version, I'd try int instead of bit (though that will result in 8 for nulls).
0
 
LVL 13

Expert Comment

by:alpmoon
ID: 39291543
I think this what you need (just nullable columns):

select o.name as tableanme, c.name as columnname
from syscolumns c
join sysobjects o
on c.id = o.id
where o.type = 'U'
  and object_name(o.id) = 'Your_table'
  and status & 8 = 8
order by c.name
0
 

Author Closing Comment

by:Neilgordo
ID: 39292274
using latest version of sybase so solution works perfectly, thanks
0

Featured Post

Enroll in September's Course of the Month

This month’s featured course covers 16 hours of training in installation, management, and deployment of VMware vSphere virtualization environments. It's free for Premium Members, Team Accounts, and Qualified Experts!

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Whoever said that “a picture is worth one thousand words” observed a fact that can dramatically affect your marketing success. Most people tend to learn visually, so many publishers commonly acknowledge the effectiveness of visual learning by using…
Instead of error trapping or hard-coding for non-updateable fields when using QODBC, let VBA automatically disable them when forms open. This way, users can view but not change the data. Part 1 explained how to use schema tables to do this. Part 2 h…
In this video, Percona Solution Engineer Rick Golba discuss how (and why) you implement high availability in a database environment. To discuss how Percona Consulting can help with your design and architecture needs for your database and infrastr…
In response to a need for security and privacy, and to continue fostering an environment members can turn to for support, solutions, and education, Experts Exchange has created anonymous question capabilities. This new feature is available to our Pr…

715 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question