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From: Gnarlodious on 5 Feb 2010 13:44
Every time I say something like:

connection=sqlite3.connect(file)

sqlite creates a new database file. Can this behavior be suppressed
through SQLite? Or am I forced to check for the file existing first?

-- Gnarlie
From: Aahz on 5 Feb 2010 18:08
In article <6cf467a9-99d7-4fda-99da-075b4b38e3e0(a)k6g2000prg.googlegroups.com>,
Gnarlodious <gnarlodious(a)gmail.com> wrote:
>
>Every time I say something like:
>
>connection=sqlite3.connect(file)
>
>sqlite creates a new database file. Can this behavior be suppressed
>through SQLite? Or am I forced to check for the file existing first?

Check first
--
Aahz (aahz(a)pythoncraft.com) <*> http://www.pythoncraft.com/

import antigravity
From: Roger Binns on 8 Feb 2010 03:11
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Gnarlodious wrote:
> Every time I say something like:
>
> connection=sqlite3.connect(file)
>
> sqlite creates a new database file. Can this behavior be suppressed
> through SQLite? Or am I forced to check for the file existing first?

This is due to the API that pysqlite uses to talk to SQLite. (There is a
more recent API but pysqlite remains backwards compatible with older SQLite
versions).

Note that although SQLite will create the file, it will be zero length (*)
until you do a command that causes a database change.

Also as a guideline be careful with SQLite files. In particular not only is
there a database file, but there may also be a journal file. If the journal
is removed then the main database file can be corrupted. (The journal
contains data in order to rollback back incomplete transactions from the
database.)

(*) On Mac due to an operating system bug the file will actually be created
as one byte in length containing the upper case letter 'S'.

There is a dedicated mailing list for Python and SQLite:

http://groups.google.com/group/python-sqlite

You can use the newer SQLite database open API as well as many other SQLite
APIs not supported by pysqlite by using APSW. (Disclaimer: I am the author
of APSW.)

Roger
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