What do column constraints actually do?

[Joseph Harvey]

While configuring boards in JIRA Agile, I've noticed the ability to set column constraints. However, I've not been able to work out what effect they have; The administrator documentation describes how to configure them, but doesn't describe what the effect of their being exceeded actually is.

Possibly I've just missed some crucial line somewhere. If so, where is the line - and if not, what would the line be, if it existed?

[Martin Böhme · Accepted solution]

As Nic explained and later specified:

A column with Column Constraint: Issue Count or Issue Count, excluding sub-tasks will warn you when you try to move an issue into that column if it is already too full. It will not prevent you from doing it, though.

[Nic Brough -Adaptavist- · Accepted solution]

They prevent cards being dragged into the column when it's going to overflow. Let's say you're using story points and you set a limit of 10. You've got a pile of cards, all with story points set to 3 - you can drag the first three into the limited column, but not the fourth because that would take the total from 9 to 12.

[Nic Brough -Adaptavist-]

No, for exactly the reasons you state - not allowing "new" issues would be a bit of a bust. Equally, would you really want to limit what you can move into "done", just because you set a limit?

I have not actually experimented with this, but the docs (and, common sense!) strongly imply that column limits only apply to "in progress" columns.

[Joseph Harvey]

Does that extend to preventing the creation of new items? I ask because I'm using JIRA Agile primarily for bug reports, and preventing new bugs from being reported seems like a bad policy.

[Joseph Harvey]

Ah, your answer is based on speculation?

[Nic Brough -Adaptavist-]

No. I have seen the constraints work for "in progress". I have never had a problem adding lots of new issues into a "new" column or moving lots of issues into a "done" column. The docs imply that it's only in-progress that's affected. I just haven't tested it with constraints in mind.

"entirely on speculation" isn't quite right, it's more "everything says it works this way, it seems to and I've not run into a case where it doesn't, but I've not deliberately set up a test for it"

[Joseph Harvey]

OK. Do you have a link to the documentation that describes this behaviour? Is it assumed that the behaviours are different when constraints are applied to thse columns, or are users trusted to only apply constraints to columns where they make sense? And do you happen to know if constraints affect behaviour in any other way, such as firing off notifications when the constraints are met or exceeded or indicating that constraints have been met in some view or other?

[Nic Brough -Adaptavist-]

Remember that only project admins can set constraints, they're useless if the ordinary users can botch them to suit themselves.

The standard documentation is far better written that anything I'd write. See https://confluence.atlassian.com/display/AGILE/Configuring+Columns

The constraints really are (deliberately and rightly) mininmal, they stop you overloading a column. Nothing else happens.

[Joseph Harvey]

What you have said has been much more useful than the official documentation.

That documentation doesn't actually say what the constraints do; It defines them as specifying how many issues a column can contain, but it doesn't say whether JIRA actually prevents items being added to a column, or just gives a warning when you do or try. It also doesn't describe whether and how minimum constraints act differently to maximum constraints, nor whether constraints can feed into any other of JIRA Agile's behaviours.

So, thanks for all your help! You've explained lot I wouldn't have been able to find out otherwise.

[Joseph Harvey]

After some experimentation, I have discovered that your answer is in fact completely wrong: Column maximums do not prevent cards being dragged into columns.

[Nic Brough -Adaptavist-]

Sorry, I wasn't clear. They won't stop you doing it (without code), but they highlight the column has a problem by going very red.