Ps = conn.createPreparedStatement( 'update tab set lob =?') In the 10.2 driver, we can treat Clob as if they were strings, with code like: For small Strings, this is a huge overhead. This is justified for large (Mb or larger). Better yet: do not code them yourself, use JPublisher to create Oracle object classes. Do not code your own CustomDatum classes for mapping complex types from SQLĭo not use CustomDatum at all (deprecated since 9i, 6 years ago). SQL Injection – where the server mistakes data for codeīreaks the benefit of caching – and therefore hurts performance!ħ. Instead: preparedStatement() with bind parameters In other words: do not use stmt=conn.CreateStatement() Do not concatenate conditions to SQL statement – instead use bind parameters Which is much worse in terms of performance.Ĩ. Instead: conn.prepareStatement(' select * from tab where id =?') Ĭonn.prepareStatement(' select * from tab where id =:1') Do not use integer (named) arguments conn.prepareStatement(' select * from tab where id =:1') But it hurts performance! Most are not at that ragged edge of representation.īringing the number into Java is much faster than using the Oracle Number.ĩ.

If that precision really matters – you can use. Oracle representation is a huge (38 byte) type. Whenever JDBC will do the job (today) the Oracle extension will eventually go away.Įxception: NUMBER. Oracle now optimizes for JDBC, not for its own extensions if there is a choice. Now instead you should use standard Java JDBC types! Most Oracle extensions are from the time that JDBC was much smaller and more limited.

Long time ago these types were created to improve performance (represent exactly what comes of the wire). (Note: 30 minutes onwards, Doug is still happily sharing his expertise, telling tales from the depths of the JDBC arena, with a small audience hanging on to his every word.)ġ0. Oracle JDBC Driver 10gR2 can be used with any supported database version so there is no good reason for not using the latest version of the JDBC drivers, even for organisations working with 8i or 9i databases. One thing that is very clear to me is that a good understanding of the JDBC drivers – and recent changes in them – can be very useful to put it mildly for improving our applications.Īnother very important conclusion: the versions of the Oracle JDBC driver and the Oracle database are not tied together. I will try to sum them up as I understand them. In a very powerful delivery, Douglas discussed the ten worst practices – and their proper counterparts – with the use of the Oracle JDBC drivers. I just came out of – well actually, as I am writing this down I am still in it – a very good session on the Oracle JDBC drivers by Douglas Surber, principal developer for Oracle JDBC Drivers.

Ojdbc7 vs ojdbc8