sqlalchemy double quoting list items - list

Question

I'm have a quoting issue with raw query when using "WHERE IN" statement. SQLAlchemy is adding double quotes around single quotes in a list...
Query that i'm trying to execute
sql_query = "SELECT col1, col2, col3 FROM preferences WHERE recipient IN :recipients"
preferences = sqlsession.execute(sql_query,dict(recipient=tuple(message.recipients))
message.recipients is a list like so:
["recipient1","recipient2","recipient3"]
SQLAlchemy debug log
INFO:sqlalchemy.engine.base.Engine:SELECT col1, col2, col2 FROM preferences WHERE recipient IN %s
INFO:sqlalchemy.engine.base.Engine:(('recipient1', 'recipient2', 'recipient3'),)
Mariadb log
9 Query SELECT col1, col2, col3 FROM preferences WHERE recipient IN ("'recipient1'", "'recipient1'", "'recipient1'") <-- double quotes around single quotes
I have run strace to see where those quotes are added and it's sqlalchemy fault.
Table schema:
CREATE TABLE `preferences` (
`recipient` varchar(255) COLLATE latin1_general_ci NOT NULL,
`col1` tinyint(1) NOT NULL DEFAULT '1',
`col2` tinyint(1) NOT NULL DEFAULT '1',
`col3` tinyint(1) NOT NULL DEFAULT '1',
PRIMARY KEY (`recipient`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1 COLLATE=latin1_general_ci
Environment
CentOS 7
python-sqlalchemy.x86_64 0.9.7-3.el7 epel

Answer 1

Hi.
As proposed on the gmane.comp.python.sqlalchemy.user, you could use the autoload feature.
To summarise Michael Bayer answer:
t = sqlalchemy.Table(
'preferences', # your table name
sqlalchemy.MetaData(),
autoload=True,
autoload_with=sqlsession,
)
query = sqlalchemy.select([t.c.col1, t.c.col2, t.c.col3]) \
.where(t.c.recipient.in_(message.recipients))
preferences = query.fetchall()
In my case I would had to "autoload" a bunch of tables, and it was not really convenient as they had complex joins.
I ended using something in the lines:
query = "SELECT col1, col2, col3 FROM preferences\nWHERE recipient IN (%s);" % (
', '.join(['%s'] * len(message.recipients)
)
result = sqlsession.execute(query, (message.recipients,)) # notice the ","
The idea is to build the query with the number of items which will be given to the IN expression; by doing so you will have the benefits of the auto-escaping functionality and be compatible with all databases backends (as far as I know).
You can see the resulting query with:
>>> print result._saved_cursor._last_executed
SELECT col1, col2, col3 FROM preferences
WHERE recipient IN ('recipient1', 'recipient2', ...);