Hi Michael,
We already tried to explain the Oracle query execution plan with our DBA.
The result is that the Oracle server prefers to make a full table scan
instead of using the index; the reason is still indeterminate (the database
statistics are up to date), we checked arguments data type and as
Hi,
Maybe you’ve run into this:
https://groups.google.com/forum/#!topic/sqlalchemy/8Xn31vBfGKU
Gabor
From: sqlalchemy@googlegroups.com [mailto:sqlalchemy@googlegroups.com] On
Behalf Of Thierry Florac
Sent: 12 May 2014 23:13
To: sqlalchemy
Subject: [sqlalchemy] Oracle index not used
On May 13, 2014, at 4:21 AM, Thierry Florac tflo...@gmail.com wrote:
Hi Michael,
We already tried to explain the Oracle query execution plan with our DBA. The
result is that the Oracle server prefers to make a full table scan instead of
using the index; the reason is still indeterminate
Hi Michael,
I just tried using literal_column function and now performances are as
good as they can :-/
As my problem is only limited to a single use case, using this method, even
if not perfect (arguments must be carefully verified!), if far better than
a global option.
Many thanks,
Thierry
Hi,
I use Python and SQLAlchemy to access an Oracle 11 database. As far as I
think, SQLAlchemy always use prepared statements.
On a huge table (4 millions records), correctly indexed, SQLAlchemy filters
queries doesn't use the index, so doing a full table scan is very slow ;
using the same SQL
On May 12, 2014, at 6:12 PM, Thierry Florac tflo...@gmail.com wrote:
Hi,
I use Python and SQLAlchemy to access an Oracle 11 database. As far as I
think, SQLAlchemy always use prepared statements.
SQLAlchemy has no control over this as the DBAPI has no prepared statement
system exposed