Description

The @SnapshotScan system procedure provides information about any native snapshots that exist within the specified directory path for all nodes on the cluster. The procedure reports the name (prefix) of the snapshot, when it was created, how long it took to create, and the size of the individual files that make up the snapshot(s).

@SnapshotScan does not include CSV format snapshots in its output. Only native format snapshots are listed.

Return Values

On successful completion, this system procedure returns three VoltTables providing the following information:

The first table contains one row for every snapshot found.

The second table contains one row for every host.

The third table contains one row for every file in the snapshot collection.

If the system procedure fails because it cannot access the specified path, it returns a single VoltTable with one row and one column.

Examples

The following example uses @SnapshotScan to list information about the snapshots in the directory /tmp/voltdb/backup/.

$ sqlcmd
1> exec @SnapshotScan /tmp/voltdb/backup/;

The following program example performs the same function, using the VoltTable toString() method to display the results of the procedure call:

VoltTable[] results = null;

try { results = client.callProcedure("@SnapshotScan",
                       "/tmp/voltdb/backup/").getResults();
}
catch (Exception e) { e.printStackTrace(); }

for (VoltTable t: results) { 
   System.out.println(t.toString()); 
}

In the return value, the first VoltTable in the array lists the snapshots and certain status information. The second element of the array provides information about the directory itself (such as used, free, and total disk space). The third element of the array lists specific information about the individual files in the snapshot(s).