Performance problems with blobs

matej · Post by **matej** » Tue 14 Feb 2006 08:57

I have performance "problems" with reading tables with blobs. With same data, and field type "long", it works much much faster.

So I've done some test with ODAC and ADODB (oracle) driver (oracle 10G server). I've tested reading data from tables with blob/long field type. Data in tables was same.

Reading speed:
ADODB (Oracle driver):
Table with BLOB: ~6600 ms.
Table with LONG: ~18000 ms

ODAC (without NET option):
Table with BLOB: ~13000 ms
Table with LONG: ~750 ms

ODAC (with NET option):
Table with BLOB: ~7000 ms
Table with LONG: ~750 ms

So I have questions. Why is reading speed of LONG type field much better then BLOB (I don't like to use LONG type, becose it is obsolete), and why is reading speed of blob slower then ADODB driver (especialy with oracle client/without NET option).

Matej

Challenger · Post by **Challenger** » Wed 15 Feb 2006 15:25

We performed the same tests but got other results. Please send precise description of your tests and small sample project including script to create server objects to ODAC support address.