[Zope-DB] DCOracle2.1.1 problems
Matthew T. Kromer
Mon, 15 Jul 2002 10:09:17 -0400
Johannes Heinz wrote:
>I have just upgraded from DCOracle1.3.2 to DCOracle2.1.1 and
>the following problems:
>calling a stored procedure with lob_support leads to hanging
>as if the description isn't gotten correctly,
>other stored procedures seem to work.
>(we did not change stored procedures).
>The call is:
>(with c as a cursor)
There were some LOB fixes checked into CVS within the last couple of
months; I'd get the latest CVS copy (I havent done a source 'release' in
a while). That may help. If I recall, one of the things fixed was
BLOB and CLOB OUT values from stored procedures.
>Using Lob functions in the form:
> c.execute('select LENGTH,INHALT_LOB from %s where DOCNUM=%s' % (tablename,docnum))
> while restlength>1000:
>leads to ORA-03127 with the first occurence of lob.read
>("no new operations allowed until the active operation ends")
Here's what the error guide has to say about that message:
ORA-03127 no new operations allowed until the active operation ends
Cause: An attempt was made to execute a new operation before the active
non-blocking operation completed or a new operation was attempted before
all the pieces of a column were inserted or fetched.
Action: Execute the new operation after the non-blocking operation
completes. If piecewise binds/defines were done, execute the new
operation after all the pieces have been inserted or fetched.
I suspect the nonblocking operation in question is due to the way you're
reading 1000 bytes at a time out of the LOB. If you do a lob.read() you
should slurp the entire contents of the lob at once, which may make that
problem go away.
DCOracle2 does piecewise binds only for LONG colums, not LOBs, but I
expect the problem has to do with some kind of lingering on the LOB.
>A select query of an empty string field in the Oracle Database
>returns the string text "None" (!!!) instead of a None object or an empty string!!!
>Could you please tell me, if I have made something wrong or if this is a bug
>(known or unknown or probably yet solved)?
I'm not aware of anything like that -- it sounds like something is doing
a str() on a value of None. I'd double-check the invoking code to see
if it's turning results into strings before printing -- nothing in the
DCOracle2 code does that.
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