On Sun, 28 Nov 2010, Marco van de Voort wrote:
On Wed, Nov 24, 2010 at 08:57:48PM +0100, Michael Van Canneyt wrote:
The SQLDB model is in fact modeled after Firebird.
Firebird offers more control over the transactions.
We did not want to take away this possibility, so we modeled sqldb on
the most powerful RDBMS. This adds some overhead for the others.
Could you give some examples about this? postgres vs firebird?
Examples of what exactly ?
In Postgres (and in fact most other engines), you have essentially
1 simultaneous transaction per connection. (implicit or explicit).
When running a query, you must simply specify the connection;
The transaction context is automatically known. There is no way to alter it.
Transaction control is limited to BEGIN; COMMIT; and SAVEPOINT.
(a bit overimplified, but essentially that is it).
Firebird allows you to have multiple transactions simultaneously per connection.
So when running a query, you must always specify
- Database handle
- Transaction handle
This is in fact very convenient in a multi-tier server app:
There can be 1 connection to the database, but all logged-in
users operate in their own transaction context.
User A commits something, and this has no effect whatsoever on what user B is doing.
Michael.
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