Subject RE: [firebird-support] Re: Grants query
Author Alan McDonald
> Hi Alan!
> To me, it seems like a strange requirement to give someone UPDATE
> permission without SELECT permission. But given that this is the

then why doesn't update permission give sufficient rights to update? i.e. to
select "enough" to update? Giving update permission should give update
permission. If update does nothing without select what's the purpose?

> situation, I can well understand why they cannot use a WHERE clause
> without the SELECT permission:
> Suppose Robin Hood wanted to check whether you were a suitable victim,
> but only had UPDATE rights to the Employee table. If he could update
> with a WHERE clause, he could simply do
> UPDATE Employee
> WHERE Name = 'Alan McDonald'
> AND Salary > '50000'
> AND Debt < '30000'
> If the number of updated rows then were > 0, he would know that you
> were a wealthy man, well worth robbing.

buth without select permission, this update fails if no select permission is
also granted.

> Hence, if you can use UPDATE with a WHERE clause, you would in many
> cases be able to guess things that you normally would need a SELECT
> permission to do (though it would be more cumbersome).
> Set
> --- In, "Alan McDonald" wrote:
> > Grants logic question:
> > If I want to a user to update a specific row in a table (PK), then
> > the user must have UPDATE and SELECT permissions since you use the
> > WHERE ID=? syntax.
> > But if the user doesn't have SELECT permissions, it can update ALL
> > rows, since no WHERE clause is used. Can someone explain why table
> > wide update ability is less stringent than a single row update?
> > thanks
> > Alan