By ashiwebi on

I have the records which is in Oracle and I want to migrate those records from oracle to mysql.

Is it requires to much customisation.

What are the necessary steps we need to check before importing.

Help is needed.

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Comments

peterx’s picture

peterx commented

Oracle has some non standard date formats in old releases. Some sites carry forward the old non standard formats.

Oracle has transactions and other fancy features. PostgreSQL is a better match to Oracle when you use transactions or the other fancy features. Drupal works with PostgreSQL almost as easily as MySQL. If you want stored procedures but not transactions, use MySQL 5.1.

Oracle before 8 could not handle long strings or binary data despite all the competing open source databases swallowing that type of data easier than I can eat an icecream. Oracle 8 had a real bad temporary fix to handle 4K binary strings instead of 2K binary strings. It could not handle the multimegabyte strings people were already throwing into MySQL. Oracle 9 had a bandaid on top of the crusty older bandaid to handle slightly longer binary strings. If you are using binary data in Oracle, you need to study the characterset options and collation sequences in MySQL to get a match.

petermoulding.com/web_architect

mradcliffe’s picture

mradcliffe
he/him
Primary language English
commented

I have used ora2pg in the past, and it was fairly reliable. I used this for a completely different conversion project. I had to hack into a bit to convert oracle 8 blobs and some other binary data around, but that was situation specific. We changed bytea types into hex by extracting the bytea into a file, running a custom hex dumper on it, and then reading the output back into ora2pg (this was a hack around line 1500 of version 4.5).

For large sets of data it may take several hours. IIRC, it took 22 hours to run a script on all tables that I had with lots of data (multiple tables with millions of rows). This was Oracle 8 -> Postgresql 8 from an old Oracle server.

The script did crash perl on me several times, but again I think that was a specific case.