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RE: Rebuilding database to change block size

From: <>
Date: Tue, 6 Jun 2000 11:10:20 -0500
Message-Id: <>

You will find the database create statement in the trace file (backup control file to trace)

You wanted to change some parameters so I think it would be good if can pre-create all the tablespaces and size them properly.

Everything else looks good.


-----Original Message-----
From: Miller, Jay [] Sent: Tuesday, June 06, 2000 11:51 AM
To: Multiple recipients of list ORACLE-L Subject: Rebuilding database to change block size

Okay, we finally got enough storage space to hold an export of our datawarehouse so I'm going to change the block size from 4 to 16.

Obviously I'm testing this on a small play database first, but I've never done this before so I have several questions and would welcome any advice/comments/criticisms. Here's what I was thinking of:

  1. Do a full export (consistent=y) as sys. Backup control file to trace
    (just as an extra precaution).
  2. Shutdown database.
  3. Cold backup of all files.
  4. Drop all datafiles,control files, redo logs. Any other cleanup necessary? Or since the CREATE DATABASE command will erase data in existing datafiles, can I just skip this step entirely?
  5. Change db_block_size in init.ora file
  6. Start database in NOMOUNT mode.

Here's where I'm on somewhat thinner ice: 7. Issue create database command. Is there a way to generate this automatically from the existing database? It's easy enough to write from scratch but I'd rather not take chances with typos if I don't have to.

8. Change sys and system passwords.
9. I definitely want to precreate a few tablespaces where I want to change the initial extent parameter. Is it necessary to precreate all tablespaces and users (I can generate that script very easily)

  1. Import database as sys.

Okay, what am I missing?

Thanks to all,

Author: Miller, Jay

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Received on Tue Jun 06 2000 - 11:10:20 CDT

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