SYSCS_UTIL.VALIDATE_TABLE_BACKUP

The SYSCS_UTIL.VALIDATE_TABLE_BACKUP system procedure validates a table backup by checking for inconsistencies; it reports on missing files and bad checksum values.

Syntax

SYSCS_UTIL.VALIDATE_TABLE_BACKUP( VARCHAR schemaName,
                                  VARCHAR tableName,
                                  VARCHAR directory,
                                  BIGINT  backupId,

schemaName

The name of the table’s schema.

tableName

The name of the table whose backup you want to validate.

directory

Specifies the path to the directory containing the backup you want to validate. This can be a local directory if you’re using the standalone version of Splice Machine, or a directory in your cluster’s file system (HDFS or MapR-FS).

Relative paths are resolved based on the current user directory. To avoid confusion, we strongly recommend that you use an absolute path when specifying the backup location.

backupId

The ID of the table backup job from which you want to restore your table.

Results

This procedure does not return a result.

Execute Privileges

If authentication and SQL authorization are both enabled, only the database owner has execute privileges on this function by default. The database owner can grant access to other users.

SQL Example: Backup, Validate, and Restore a Table

This example shows you how to back up a table, then validate and restore it, in these steps:

Backing Up the Table

This command line performs a full backup of the TPCH100 LINEITEM table to the /backup directory on HDFS:

splice> CALL SYSCS_UTIL.SYSCS_BACKUP_TABLE('TPCH100', 'LINEITEM', '/backup', 'full');
Success
----------------------
FULL backup to /backup

1 row selected

See the reference page for the SYSCS_UTIL.SYSCSBACKUP_TABLE system procedure for more information about backing up a table.

Examining the Backup

After the backup completes, you can examine the sys.sysbackup table to find the ID of our new backup:

splice> SELECT * FROM sys.sysbackup;
BACKUP_ID      |BEGIN_TIMESTAMP          |END_TIMESTAMP            |STATUS     |SCOPE     |INCR&|INCREMENTAL_PARENT_&|BACKUP_ITEM
-----------------------------------------------------------------------------------------------------------------------------------
587516417      |2018-09-25 00:12:33.896  |2018-09-25 00:42:53.546  |SUCCESS    |TABLE     |false|-1                  |3

You can use the ID of your backup job to examine the sys.sysbackupitems and verify that the base table and two indexes have been backed up:

splice> SELECT * FROM sys.sysbackupitems WHERE backup_Id=587516417 ;
BACKUP_ID   |ITEM             |BEGIN_TIMESTAMP           |END_TIMESTAMP
-----------------------------------------------------------------------------------------
587516417   |splice:292000    |2018-09-25 00:12:40.512   |2018-09-25 00:32:14.856
587516417   |splice:292033    |2018-09-25 00:12:40.513   |2018-09-25 00:42:48.573
587516417   |splice:292017    |2018-09-25 00:12:40.512   |2018-09-25 00:41:25.683

3 rows selected

Validating the Backup

Before restoring the table, you can validate the backup:

splice> CALL SYSCS_UTIL.VALIDATE_TABLE_BACKUP( 'TPCH100', 'LINEITEM', '/backup', 587516417 );
Results
---------------------------------------------------------------------------------------------
No corruptions found for backup.

1 row selected

Restoring the Backup

You can restore the table to another table on the same cluster, or on a different cluster.

This command restores the backed-up table to table named LINEITEM in the SPLICE schema:

splice> CALL SYSCS_UTIL.SYSCS_RESTORE_TABLE('SPLICE', 'LINEITEM', 'TPCH100', 'LINEITEM', '/backup', 587516417, false);
Statement executed.

See the reference page for the SYSCS_UTIL.SYSCS_RESTORE_TABLE system procedure for more information about restoring a backed-up table.

See Also