Sets a list of databank shadows offline or online, with the option of clearing the
LOGDBrecords for them.
Setting a databank shadow
OFFLINEsuspends updating of it. A typical use for this is when taking databank backups from shadows using the host file system.
When a databank shadow is set
ONLINEagain, you must specify whether:
- to clear the applicable
LOGDBrecords using the
- or whether to preserve these (using the
RESET LOGoption after a successful backup has been taken.
Clearing records from
LOGDBis handled automatically when
CREATE BACKUPis used to take databank backups.
The current ident must either be the creator of the databank to be shadowed, or have
BACKUPprivilege in order to use all the
If the current ident holds
SHADOWprivilege, the shadow can be set offline and online with the
PRESERVE LOGoption, but the
RESET LOGoption cannot be used.
SET SHADOWcannot be used if the master databank is
While a shadow is
OFFLINE, updating of it is suspended. It is possible to use
ALTER SHADOWto change the shadow while it is
ALTER SHADOWwas used to change the location of the shadow file while the shadow was
SET SHADOWstatement will verify that the new file contains a valid copy of the shadow when the shadow is set
ONLINEagain (it cannot, however, check that the contents of the file is up-to-date).
It is possible to use
DROP SHADOWto drop an
SET SHADOW OFFLINEwill succeed with a warning if the shadow exists and is
ONLINE, but the file cannot be accessed for some reason.
It is not possible to set more than a single shadow of any given databank
OFFLINEat a time. If the
shadow-listcontains more than one shadow for a databank, none of the shadows for that databank will be set
OFFLINE, and an error will be raised.
An error will be raised if an attempt is made to set a shadow
OFFLINEthat is already
ONLINEwhen it is already
ExampleSET SHADOW MIMER_STORE$SHADOW_1, MIMER_STORE$SHADOW_2 ONLINE RESET LOG;
For more information, see the Mimer SQL System Management Handbook, Mimer SQL Shadowing.
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