alex bodnaru wrote:
> hi jason,
>
> On Mon, Sep 8, 2008 at 6:45 PM, jason kirtland <[EMAIL PROTECTED]> wrote:
>> alex bodnaru wrote:
>>> hello friends,
>>>
>>> i wanted to do a few sql commands in a ddl construct, but i failed with:
>>>
>>> pysqlite2:dbapi2 warning: you can execute one statement at a time
>>>
>>> i'm not very familiar with python db layer, but i know sqlite may be invoked
>>> specifically to execute one, or many statements divided by ';', so i suspect
>>> it's specifically invoked for one statement.
>>>
>>> while this is a good security measure for sql from untrusted sources, like
>>> user
>>> input, it's quite annoying for a situation where free sql should be
>>> specifically
>>> added.
>>>
>>> as for my case, i had a batch of inserts based on an external file,
>>> and i couldn't
>>> invoke ddl.execute_at in a loop, so i had to switch to inserting a
>>> batch of unioned
>>> selects in one insert, which was nice to learn :).
>> The use case behind the DDL() construct is a single statement. You can
>> fire multiple statements by using multiple DDL()s. But for inserts,
>> I've found it more useful to write a 'after-create' event listener from
>> scratch. Here's one that I use in pretty much every project, in some
>> form or another:
>>
>> def fixture(table, column_names, *rows):
>> """Insert data into table after creation."""
>> def onload(event, schema_item, connection):
>> insert = table.insert()
>> connection.execute(
>> insert,
>> [dict(zip(column_names, column_values))
>> for column_values in rows])
>> table.append_ddl_listener('after-create', onload)
>>
>> Looks like this in use:
>>
>> fixture(some_table,
>> ('x', 'y'),
>> (1, 2),
>> (3, 4),
>> (5, 6))
>>
>
> thanks for your idea. it looks cool. i understand this will be
> triggered after all DDL end.
>
> but i wanted to do arbitrary sql as DDL provides, and the insert was
> just an example for a
> series of statements.
The DDL() function is just some sugar for the DDL event shown interface
above. If you want to perform more than one statement, the API is in
place for any customization you'd like.
> just wondered why would this be the place to limit to one statement:
> it isn't parsed by SA
> in any way.
SA doesn't put any limits on what SQL gets pushed through. It's passed
through directly to the DB-API execute() method. I'd guess that most
DB-API implementations will probably reject multiple statements in a
single execution.
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