DBTOOL Option 5. Read or Validate Database Blocks Validation Levels :
0: Block header info only
1: Record header & record size
2: Record overlap checking
- Validation levels are "AND", for example validation level 2 == 0 + 1 + 2.
- Typically Validation levels above 0 are only ever used when we need to delve deeper at the block level into record corruption (which would initially be reported through DBTOOL 3. Record Validation)
What blocks does DBTOOL Option 5. Read or Validate Database Blocks validate?
This Option only reads Data Blocks, there's no Index Block or LOB Block Validation
Which is why running DBTOOL Option 5 Read or Validate Database Blocks :
- May report the "Total blocks read: 0" , or less than the number of blocks that the High Water Mark for the Area. This is entirely expected when the Storage Area only or additionally contains indexes / lobs.
- After a 1124 DBDOWN, may not find database block headers corruption when a database block that contained Index or LOB. The best option to scan all database blocks in an area is to run a dummy PROBKUP. This will increase the backup counter in each database block below the HWM, but will not create a backup volume:
Windows: $ probkup [online] <dbname> NUL
UNIX: $ probkup [online] <dbname> /dev/null
Proof that DBTOOL 5. Read or Validate Database Blocks does not scan anything but DATA blocks:PROBKUP .lg
(6686)
462936 active blocks out of 492006 blocks in dbname will be dumped
(9286) Restore would require an estimated 462936 db blocks using 3.5 GBytes of media
(13625) Wrote a total of 13624 backup blocks using 3.5 GBytes of media
DBTOOL:
Read or Validate Database Blocks<area>: (Area number or all)? all (db block usage Active blocks:
462936)
Total blocks read:
380601<area>: (Area number or all)? 6 (Schema: Active blocks:
302)
Total blocks read:
65<area>: (Area number or all)? 20 (data: Active blocks:
380607)
Total blocks read:
380536<area>: (Area number or all)? 30 (index: Active blocks:
82015)
Total blocks read:
0<area>: (Area number or all)? 40 (lobs: Active blocks:
7)
Total blocks read:
0 
