Useful information
Ramesh, July 09, 2002 - 3:30 am UTC
Hi,
The answer which you provided was useful for me. I would like to know the information on how to proceed with a disconnected model method for converting Informix to Oracle.
Thanks,
July 09, 2002 - 7:20 am UTC
describe what you mean by "disconnected" model.
migration
mo, February 18, 2003 - 4:34 pm UTC
Tom:
I am migrating an informix database into oracle. Before I do that I like to define my database sizing requirements for dba correctly. Here is the stats on the informix database.
All numbers are in pages and each page is 4KB.
Physical Logs 64000
Logical Logs 64000
Data 512000 total 225667 used
Indexees 81920 total 18294 used
Temporary 5 dbspaces of 15360
Any suggestions,hints or links on how I do this?
Thank you,
February 18, 2003 - 6:50 pm UTC
I guess you would multiply the page counts by 4? Maybe divide that by 1024 so you can tell them in megabytes.
forget the physical/logical logs -- let the DBA size out the redo as they figure out the transaction rates.
informix migration
mo, February 18, 2003 - 9:56 pm UTC
Tom:
1. Are the logical and physical logs for sizing the rollback segment? How would the dba determine this based on transaction rates (is it after he monitors the database or when he initially creates database)?
2. This translates to the following megabytes:
Data = 2000 M bytes
Index = 320 M bytes
Temporary = 75 M bytes
Would you agree with creating the following 4 tablespaces:
DATA - 2000 M
TEMP - 75 M
RBS - check transaction rate
INDEX - 320 M
Would you create any others like USERS or TOOLS?
would you create 5 TEMP spaces like informix or just one?
Thank you,
February 19, 2003 - 8:44 am UTC
1) in informix -- undo and redo are stored in the logs. they would be for rollback and redo but since we are about as differently architecturally there as you can be -- their sizes are not relevant.
For example, In Oracle you do not need to size the logs big enough to hold the largest transaction. You could have 100meg of log and do a 2000meg update. Informix cannot, they would fail the transaction at 100meg.
We are very different. Please let your Oracle DBA size out the Oracle stuff -- don't confuse them with irrelevant Informix errata.
2) I aggree with anything you want to do. Go for it. that is a tiny database, you cannot go very wrong.
And again -- let your DBA take care of temp, undo, redo, the stuff they are hired for. It would not make sense to have 5 temp tablespaces, no. But -- they will know that already.
infromix migration
mo, February 19, 2003 - 9:59 am UTC
Tom:
Thanks. You just worried me with the word "Tiny" . do you mean not much data? Do you recommend adding 20% on the sizes I suggested or it is OK to have a tiny production database and expand later as needed?
February 19, 2003 - 1:50 pm UTC
No, I mean this database is so small that pretty much whatever you do can be fixed in seconds if it was wrong so tons of "thought" about optimum this that and the other isn't relevant. I can fit this on my pendrive and stick it in my pocket.
Migration reconcilation
Suresh, March 24, 2006 - 12:03 pm UTC
Hi,
This is my first post in this forum.
And this post is mainly to get help from you regarding verification of data migration .
we are in the process of migrating our database vendor from INFORMIX to ORACLE .
I need to ascertain whether the data has migrated correctly or not during my data migration process? Also if the migration is incorrect can you suggest me when and where the rectification be done, is it during data migration process or after the entire data migration process and if so how.
Suresh
March 24, 2006 - 3:31 pm UTC
how much data are you talking about.
Migration reconciliation
Suresh, March 27, 2006 - 5:52 am UTC
Hi,
Right now I do not know the exact volume of data to be migrated. But as per initial plan, data migration needs to be done from 30 separate Informix databases into a single consolidated Oracle Database.
Thanks
Suresh
March 27, 2006 - 10:01 am UTC
then, I cannot really recommend anything. Guess you could write a C program or java or whatever that connects to informix and computes a checksum using whatever algorith you want and then does the same against Oracle.
Or, you can configure the ODBC connectivity and do a distributed query (won't be fast for big stuff obviously).
infomix to Oracle migration
bhupendra, September 28, 2022 - 9:48 am UTC
do we have any reference on infomix to oracle migration?
What is best approach (ODI/GG/lift and shift) ?
August 15, 2023 - 2:17 am UTC
I don't know of anyone that has does for a few years now.
I'm no expert in the area, but I'd probably be looking an one-off dump-and-load, and some goldengate if necessary to copy deltas
https://docs.oracle.com/goldengate/1212/gg-winux/index.html (Not sure if our latest GG even supports it)