Re: Data migration from informix to oracle 10g R2
Date: Sun, 30 Dec 2007 11:57:40 -0800 (PST)
On 29 dic, 14:50, hpuxrac <johnbhur..._at_sbcglobal.net> wrote:
> On Dec 28, 3:16 pm,chijar<chi..._at_gmail.com> wrote:
> > Thanks for your answers my dear friends...
> > ...but it looks that i don't explain well...
> > Let see...
> > Enterprise 1: send me 23 plain text files monthly and this files
> > contains a lot of rows, sometimes this files could contain millions of
> > rows. Each file corresponding to one table. This files have 30 Gb of
> > total size, that means that one file could have 2Gb or 1Gb of size.
> > I don't have any type of access to source database (informix).
> > Enterprise 2: (my office): after i receive files, i have to upload
> > this data to my database (with workbench, sqlloader, or ¿external
> > files?)
> Are these files going to add into existing contents of the tables or
> are they going to be complete replacements of all the data in each
> If the files completely replace everything then one way to approach
> something like this is to proceed like this ...
> 1) drop the schema owner from the oracle database
> 2) re-create the schema owner in the oracle database
> 3) define the tables and ( perhaps primary key indexes )
> 4) use sqlldr to populate the tables ( or use external tables )
> 5) define any extra indexes needed for your application at "Enterprise
> 2 aka your office". ( Yes I think you need to understand the SQL you
> will be running and look at what additional columns might need
> indexing besides primary keys ).
> 6) generate statistics for the tables or default to letting oracle
> decide when and how ( long topic here )
> 7) define any referential integrity constraints between the tables
> 8) get a backup of the oracle database
> If you will adding in additional info to existing tables then maybe
> you want something that drops indexes, does the loads, then puts
> indexes back on. Somewhat dependent on how ref integrity comes into
> play or not, etc.
> > The purpose of this oracle database (target), is only, and only
> > selects, neither DML. i didnt' have the point of indexes and i don't
> > think that enterprise 1 send me index. Or do you recommend me that i
> > should ask for indexes DDL scripts? and what another things i should
> > to ask ?
> Depends on how you will be querying it but yeah you probably need to
> think about indexing.
> > The data type is only char, varchar, and integer data, all tables will
> > belonging to one schema.
> Then migrating memo fields into blobs in oracle is something you won't
> have to worry about.
> > I hope it was clearly. and i appreciate a lot your help.
> > cesar.
> Often in posting in cdos the more details you can supply the more you
> will receive good answers.
Really, really thanks for your answers my friends, i will begin to do
something about that, like question or investigate more about it. and
obviusly i will post my problems or solutions in order to help
thanks a lot. Received on Sun Dec 30 2007 - 13:57:40 CST