Re: try pattern for database connection with the close method

[Mark Lawrence]

On 21/02/2015 02:42, Mario Figueiredo wrote:

Hello all,

I'm using the following pattern for db access  that requires me to
close the connection as soon as it is not needed:

         import sqlite3 as lite

         try:
             db = lite.connect('data.db')
         except lite.DatabaseError:
             raise OSError('database file corrupt or not found.')
         else:
             try:
                 with db:
                     db.execute(sql, parms)
             except lite.IntegrityError:
                 raise ValueError('invalid data')
             finally:
                 db.close()

Since it's a bit verbose, is there a better way?

Note: The user of this API has the whole database functionality
abstracted away. Hence the exception channeling in the except clauses.

Use your context manager at the outer level.

import sqlite3 as lite

try:
    with lite.connect('data.db') as db:
    try:
        db.execute(sql, parms)
    except lite.IntegrityError:
        raise ValueError('invalid data')
except lite.DatabaseError:
    raise OSError('database file corrupt or not found.')

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what you can do for our language.

Mark Lawrence

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