Re: pysqlite design decisions

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

Roger Binns wrote:
> [...] I am also baffled at the behaviour of pysqlite swallowing exceptions in
> callbacks (eg user defined functions).
> 
> === pysqlite ===
> 
> from pysqlite2 import dbapi2 as sqlite
> def badfunc(t):
> ~    return 1/0
> 
> con = sqlite.connect(":memory:")
> con.create_function("badfunc", 1, badfunc)
> cur = con.cursor()
> cur.execute("select badfunc(3)")
> 
> $ python func.py
> Traceback (most recent call last):
> ~  File "func.py", line 8, in ?
> ~    cur.execute("select badfunc(3)")
> pysqlite2.dbapi2.OperationalError: user-defined function raised exception

By adding this:

sqlite.enable_callback_tracebacks(1)

You get more tracebacks printed to stderr when errors happen in callback
functions (functions, aggregates, authorizers, etc.).

There once was a good reason for doing it this way, but I forgot what
exactly it was ;-) It had something to do with another error masking the
original one in some cases, IIRC.

> The next release of APSW (corresponding to SQLite 3.3.8) has these updates:
> 
> - Dummy frames from C code in exception tracebacks
> - String values with embedded nulls work (eg "foo\0bar") rather than
> truncating at the \0
> - You can load SQLite shared library extensions
> - Support for SQLites virtual tables
> http://www.sqlite.org/cvstrac/wiki?p=VirtualTables
> 
> The virtual tables are an IMHO very interesting.

They would sure be fun to use from Python, I'd really like to play with
them. I even started implementing them in pysqlite, but it's a lot to wrap
and will take a quite some time.

If we could integrate APSW and pysqlite in such a way that I could
implement virtual tables on pysqlite connections, that would be really
great. Basically what we'd need is some way that APSW could make sense of a
pysqlite connection object and use its sqlite3* handle. Do you think that's
feasible?

- -- Gerhard
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.3 (GNU/Linux)
Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org

iD8DBQFFdfTEdIO4ozGCH14RAr7KAKCMm3plFvMnu9ZKBWEAj772+FLaJgCcDfWi
/pELEcNVtPqwRHYs2pOcWsw=
=tf/n
-----END PGP SIGNATURE-----