Re: Export Questions - Large DB

well while your are at it.
If you use >7.2 build your indexes with option urecoverable. That will speed up your indexcreation.
Best regards.
Carl Bruhn.

Peter Stryjewski wrote:

> Background:
> Using exp/imp to migrate database between two UNIX machines (IBM->Sun,
> etc) or UNIX -> NT.
> Database mostly consists of a single large table (30M+ rows).
>
> Solutions so far:
> Use "compress on the fly" with pipes for exp/imp.
> Use indexfile to build tables, import data (no indexes), build indexes.
> (Used because initial extent size for tables usually needs to be fiddled
> with or tables being built in a different tablespace that they came
> from).
>
> Questions?
> I read in Deja News that using pipes slows down the process, because the
> pipe file size is usually only 8K. I haven't really seen this problem.
> Does this slow down the process?
>
> For speed should I "compress" out of the pipe or 'split' out of the pipe
> if I have disk space?
>
> *** Can I "thread" this process? ***
> That is:
> 1) export from source using pipes and split into "chunks" (maybe
> compressed)
> 2) Transfer first chunk to target system.
> 3) cat chunk* through pipe into import command
> 4) continue exporting, transferring, importing
>
> Problems-
> Initially don't know how many chunks (thus filenames) there will be to
> import. 'cat' could bomb.
> Can't use imp with the indexfile option, because it reads through the
> exportfile too fast (not all chunks are available).
>
> *** Is using rsh to transfer the data during export cleaner/faster? ***
> How "stable" is this process? It could cut down time drastically, if we
> could multitask the export and import.
>
> Do I loose significant speed using the create table, import data, build
> indexes process? I allows flexiblity. I can easily modify table and
> index create command for initial/next extent for the new platform. If
> it pukes on an index create (not enough temp tblspace), I can drop and
> restart the index create easily. What am I loosing?
>
> For NT are there similar processes?
>
> Pete Stryjewski
> pstryjew_at_worldnet.att.net
Received on Wed Feb 03 1999 - 04:15:37 CST