Re: [Pypgsql-users] Decoding resultSet

[Gerhard <ger...@gm...>]

Le 09/03/02 à 12:31, Ellen Spertus écrivit:
> I'm having trouble decoding a resultSet from a query:
> >>> from pyPgSQL.libpq import *

libpq is the low-level API. If you don't have a good reason to use it,
don't :) Much better is to use the DB-API interface in pyPgSQL.PgSQL.
Then, you can also stay fairly portable across databases.

> [snip]

Using the DB-API interface, your code would look like:

from pyPgSQL import PgSQL

# Connect to the default database with database=user=$USER
db = PgSQL.connect()
# using no default values:
# PgSQL.connect(host=..., database=..., user=..., password=...)

# Create a cursor object (that is implicitely wrapped in a transaction)
cursor = db.cursor()

# Execute the query
cursor.execute("select count(*) from test")

# Fetch one row (here, the only one) from the resultset,
# and select the first column from that row
numrows = cursor.fetchone()[0]

> [...] Also, can anyone point me to any documentation for pypgsql?  I
> haven't been able to find it.

AFAIK the only documentation there is is in the README, the docstrings,
and the examples in the examples directory.

But as pyPgSQL "only" is an implementation of the Python DB-API 2.0 for
PostgreSQL, so you can use the documentation available for the DB-API,
for example:

- the specification itself:
  http://www.python.org/topics/database/DatabaseAPI-2.0.html
- an article by Andrew Kuchling:
  http://www.amk.ca/python/writing/DB-API.html

All documentation you can find for other DB-API modules like MySQLdb
also mostly applies to pyPgSQL.PgSQL. You only have to import a
different module and the way the connect method works differs :)

Gerhard
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