Requesting Dump Header Information

Information about database devices is stored in the dump header.

This information, along with segment maps, are used to generate a sequence of disk init, sp_cacheconfig, and disk init, create database, and alter database commands for the target database during dump image creation.

Information for each database device in the dump header block includes:

Device number
Logical name
Actual device size
Physical path
Device type
Database device size
Device options

In-memory database devices are configured using caches, and information about these caches is necessary to generate disk init and sp_cacheconfig commands to create the images. Cache-specific information is therefore stored in the dump header and includes:

Cache ID
Cache name
Database cache size
Actual cache size
Device type
Cache options

with headeronly returns the header information for a single file. If you do not specify a file name, with headeronly returns information about the first file on the tape.

The header indicates whether the dump is for a database or transaction log, the database ID, the file name, and the date the dump was made. For database dumps, it also shows the character set, sort order, page count, and next object ID. For transaction log dumps, the header shows the checkpoint location in the log, the location of the oldest begin transaction record, and the old and new sequence dates.

This example returns header information for the first file on the tape and then for the file mydb9229510945:

load database mydb
    from "/dev/nrmt4" 
    with headeronly

load database mydb
    from "/dev/nrmt4"
    with headeronly, file = "mydb9229510945"

The output from headeronly looks similar to:

Backup Server session id is: 44. Use this value when executing the 'sp_volchanged' system stored procedure after fulfilling any volume change request from the Backup Server.

Backup Server: 4.28.1.1: Dumpfile name 'mydb9232610BC8 ' section number 0001 mounted on device 'backup/SQL_SERVER/mydb.db.dump'

This is a database dump of database ID 5 from Nov 21 1992 7:02PM.

Database contains 1536 pages; checkpoint RID=(Rid pageid = 0x404; row num = 0xa); next object ID=3031; sort order ID=50, status=0; charset ID=1.