This blog contains experience gained over the years of implementing (and de-implementing) large scale IT applications/software.

HowTo: Use Oracle BBED to adjust DB Name in File Headers

HowTo: Use BBED to hack the database SID in the datafiles if you’ve gone and got them all mixed during a “CREATE CONTROLFILE” operation.

WARNING: Using BBED is not supoprted by Oracle unless you are asked to use it by Oracle Support themselves.

Use UNIX vi to create a text file that contains a line number, followed by the file name for the DB files that need changing:

# cat <<EOF > filelist.txt
1 /db/ora/system/system1.dbf
2 /db/ora/data1/data1.dbf
3 /db/ora/index1/index1.dbf

Save the file as “filelist.txt”.

Launch bbed (blockedit) as the Oracle DB UNIX owner.
Change the text “NEWID” for your new DB name in the “modify” line below.

$ bbed
BBED> set listfile 'filelist.txt'
BBED> set mode edit

# Dump the current block value for datafile #1 in your list file.
# exmaple: BBED> dump /v dba <file#>,<block> …

BBED> dump /v dba 1,1 offset 32 count 16

Make the swap:

BBED> modify /c NEWID file 1 block 1 offset 32

The checksum is now invalid:

BBED> sum file 1 block 1

Force save the new checksum:

BBED> sum file 1 block 1 apply

Verify the block:

BBED> verify file 1 block 1

Once you’ve done all your files:

BBED> quit;

Start the database with the CREATE CONTROLFILE SET DATABASE “NEWID”…