[cx-oracle-users] Strange problem with query execution...

[Thierry F. <thi...@on...>]

Hi,

I'm using cx_Oracle (actually in release 5.1.1, but with the same
symptoms in 5.1 and 5.0.4) through SQLAlchemy to access an Oracle 10g
database (release 10.2.0.4).

I'm building a web application querying a quite big table (nearly 3.5
millions records), which is indexed correctly.

After activating SQLAlchemy "echo SQL" feature, I noticed that :
 - an SQLAlchemy request takes between 10 and 15 seconds
 - the same request executed from an SQL worksheet (in Tora) is nearly
   immediate.

So I made a few tests using cx_Oracle without SQLAlchemy and the
results are that :
 - if I execute the same query with parameters (via
   "cursor.execute("select...", param1=value1,...)", which is the way
   SQLAlchemy works), it still takes between 10 and 15 seconds;
 - but if I execute the same request with "hard-coded" parameters, the
   result is immediate.

Any idea (perhaps on the DB side) ?

Thanks for any help,
Thierry
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