ALTER SNAPSHOT SET¶

Syntax¶

ALTER SNAPSHOT SET <name> ADD SNAPSHOT

ALTER SNAPSHOT SET <name> APPLY SNAPSHOT POLICY <policy_name>

ALTER SNAPSHOT SET <name> SUSPEND SNAPSHOT POLICY

ALTER SNAPSHOT SET <name> RESUME SNAPSHOT POLICY

ALTER SNAPSHOT SET <name> DELETE SNAPSHOT IDENTIFIER '<snapshot_id>'

ALTER SNAPSHOT SET <name> MODIFY SNAPSHOT IDENTIFIER '<snapshot_id>' { ADD | REMOVE } LEGAL HOLD

ALTER SNAPSHOT SET <name> SET COMMENT = '<string_literal>'

ALTER SNAPSHOT SET <name> UNSET COMMENT

Parameters¶

name

Specifies the identifier for the snapshot set.

If the identifier contains spaces or special characters, the entire string must be enclosed in double quotes. Identifiers enclosed in double quotes are also case-sensitive.

For more information, see Identifier requirements.

ADD SNAPSHOT

Manually create a snapshot in the set. If the snapshot policy doesn’t include a schedule for taking new backups, this is how you make a new backup of the table, schema, or database that’s included in the snapshot set. You can also make new backups in the snapshot set at any time even when backups happen on a regular schedule.

APPLY SNAPSHOT POLICY policy_name

Specifies the snapshot policy to attach to the snapshot set.

Important

Applying a snapshot policy with a retention lock to a snapshot set is irreversible. Due to the strong guarantees that are needed for regulatory compliance, after you put a retention lock on a snapshot set, you can’t revoke the lock. Snowflake support also can’t revoke such a retention lock. Plan carefully before you set a retention lock on a snapshot set with a long expiration period, to avoid unexpected storage charges for undeletable snapshot sets, and the schemas and databases that contain them.

If a Snowflake organization is deleted, the organization is no longer a Snowflake customer. In this case, Snowflake deletes all snapshots, including those with retention locks. Deleting a Snowflake organization requires the involvement of Snowflake support. It isn’t something that an administrator can do by accident.

SUSPEND SNAPSHOT POLICY

Suspend a snapshot policy in the snapshot set. For more information, see Suspend a snapshot policy on a snapshot set.

RESUME SNAPSHOT POLICY

Resume a suspended snapshot policy in the set. For more information, see Resume a snapshot policy on a snapshot set.

DELETE SNAPSHOT IDENTIFIER 'snapshot_id'

Delete a snapshot in the snapshot set by ID. The snapshot ID is a UUID value, in the format returned by the UUID_STRING function. For more information, see Delete a snapshot from a snapshot set.

ALTER SNAPSHOT SET name MODIFY SNAPSHOT IDENTIFIER 'snapshot_id' ADD | REMOVE LEGAL HOLD

Adds or removes a legal hold from a specified snapshot within the snapshot set. For more information about legal holds for WORM snapshots, see Legal hold. For examples of using this clause, see Add and remove legal holds.

SET COMMENT = 'string_literal'

Associate a comment with the snapshot set.

UNSET COMMENT

Remove the comment from the snapshot set.

Access control requirements¶

A role used to execute this operation must have the following privileges at a minimum:

These privileges are required on the currently active primary role, not a secondary role.

For instructions on creating a custom role with a specified set of privileges, see Creating custom roles.

For general information about roles and privilege grants for performing SQL actions on securable objects, see Overview of Access Control.

Usage notes¶

• Regarding metadata:

  Attention

  Customers should ensure that no personal data (other than for a User object), sensitive data, export-controlled data, or other regulated data is entered as metadata when using the Snowflake service. For more information, see Metadata fields in Snowflake.

Examples¶

Manually add a snapshot to snapshot set t1_snapshots:

ALTER SNAPSHOT SET t1_snapshots
  ADD SNAPSHOT;

Update the snapshot policy for snapshot set t1_snapshots:

ALTER SNAPSHOT SET t1_snapshots
  APPLY SNAPSHOT POLICY daily_snapshot_policy;

Suspend a snapshot policy on the snapshot set t1_snapshot:

ALTER SNAPSHOT SET t1_snapshots
  SUSPEND SNAPSHOT POLICY;

Resume a snapshot policy on the snapshot set t1_snapshots:

ALTER SNAPSHOT SET t1_snapshots
  RESUME SNAPSHOT POLICY;

To find the snapshot identifier to use with the ADD LEGAL HOLD and REMOVE LEGAL HOLD clauses, you typically use the SHOW SNAPSHOTS command to list the eligible snapshots and their creation times. The following example shows how you might list the appropriate snapshots, add a legal hold to one specific snapshot, and later remove that legal hold. Substitute your own role name, snapshot set name, and snapshot identifier.

USE ROLE my_legal_hold_role; -- use a role that has the APPLY LEGAL HOLD privilege
SHOW SNAPSHOTS IN SNAPSHOT SET my_db_snapshot_set
  ->> SELECT "created_on", "snapshot_id" FROM $1 WHERE "is_under_legal_hold" = 'N';
ALTER SNAPSHOT SET my_db_snapshot_set
  MODIFY SNAPSHOT IDENTIFIER '790d1ee4-88b2-451f-9ccc-eacd1e93a134'
  ADD LEGAL HOLD;

USE ROLE my_legal_hold_role; -- use a role that has the APPLY LEGAL HOLD privilege
SHOW SNAPSHOTS IN SNAPSHOT SET my_db_snapshot_set
  ->> SELECT "created_on", "snapshot_id" FROM $1 WHERE "is_under_legal_hold" = 'Y';
ALTER SNAPSHOT SET my_db_snapshot_set
  MODIFY SNAPSHOT IDENTIFIER '790d1ee4-88b2-451f-9ccc-eacd1e93a134'
  REMOVE LEGAL HOLD;