Re: [HACKERS] Specifying both recovery_target_xid and recovery_target_time

2014-01-08 Thread Tom Lane
Heikki Linnakangas hlinnakan...@vmware.com writes:
 The docs say:
 At most one of recovery_target_time, recovery_target_name or 
 recovery_target_xid can be specified

 However, the code actually allows them all to be specified at the same time:

 else if (strcmp(item-name, recovery_target_name) == 0)
 {
 /*
 * if recovery_target_xid specified, then this overrides
 * recovery_target_name
 */
 if (recoveryTarget == RECOVERY_TARGET_XID)
 continue;
 recoveryTarget = RECOVERY_TARGET_NAME;

 The precedence is XID, time, name.

 I think the documented behavior would make more sense, ie. throw an 
 error if you try to specify multiple targets. Anyone remember if that 
 was intentional? Any objections to change the code to match the docs, in 
 master?

Hm.  I can see potential uses for specifying more than one if the behavior
were OR, that is stop as soon as any of the specified conditions is
satisfied.

It looks like the actual behavior is to randomly choose one specified
mode and ignore the others, which I concur is bogus.  But maybe we
should try to do something useful instead of just throwing an error.

regards, tom lane


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Re: [HACKERS] Specifying both recovery_target_xid and recovery_target_time

2014-01-08 Thread Simon Riggs
On 8 January 2014 15:38, Heikki Linnakangas hlinnakan...@vmware.com wrote:
 The docs say:

 At most one of recovery_target_time, recovery_target_name or
 recovery_target_xid can be specified


 However, the code actually allows them all to be specified at the same time:

 else if (strcmp(item-name, recovery_target_name) == 0)
 {
 /*
  * if recovery_target_xid specified, then this
 overrides
  * recovery_target_name
  */
 if (recoveryTarget == RECOVERY_TARGET_XID)
 continue;
 recoveryTarget = RECOVERY_TARGET_NAME;


 The precedence is XID, time, name.

 I think the documented behavior would make more sense, ie. throw an error if
 you try to specify multiple targets. Anyone remember if that was
 intentional? Any objections to change the code to match the docs, in master?

It seems like I was grasping at some meaning but didn't quite achieve it.

Changing it to mean OR would make sense, but that would be more work.

-- 
 Simon Riggs   http://www.2ndQuadrant.com/
 PostgreSQL Development, 24x7 Support, Training  Services


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