On Mon, 19 Sep 2005, Iulian Popescu wrote: >Thank you very much for the answer and I apologize for my misconception. My >confusion came from the fact the database handle was used by two different >threads and one of them was executing operations inside a transaction. >Is that possible to obtain more than one handle to the same in memory >instance of the database?
I believe not. The memory database will be local to the sqlite handle. You could, however, open a file based database on a memory FS, like tmpfs on Linux or Solaris. This is a RAM based FS, backed by swap, and so is almost like a memory only database, and files created are shareble. > >Thank you, > >Iulian. > >-----Original Message----- >From: D. Richard Hipp [mailto:[EMAIL PROTECTED] >Sent: Monday, September 19, 2005 1:44 PM >To: sqlite-users@sqlite.org >Subject: Re: [sqlite] Multiple Threads and Transactions > >On Mon, 2005-09-19 at 13:27 -0400, Iulian Popescu wrote: >> Hello, >> >> >> >> I'm kind of new to the SQLite. I'm running an instance of the database in >> memory. I'm trying to figure out if the transaction isolation is also >valid >> between threads. To give a concrete example, two threads as part of the >same >> process share the same database connection. Suppose a transaction is >started >> in one thread and inserts some rows in a table A. If the same thread does >a >> SELECT * FROM A it should see the inserted records if my understanding is >> correct. What will happen if another thread does a SELECT from the same >> table A before the first thread commits the transaction? Will it see the >> records inserted by the first thread? Based on the tests I have made it >> seems to - weather I expected not. Is that correct or am I doing something >> wrong? >> >> I've noticed if I do the same thing with a database on disk and between >> processes, the second process won't see the changes until the first one >will >> commit the transaction. >> > >Isolation only occurs between separate database handles. If >you do two statements against the same database handle, they >will not be isolated. I do not understand why you would expect >that they would be. > -- /"\ \ / ASCII RIBBON CAMPAIGN - AGAINST HTML MAIL X - AGAINST MS ATTACHMENTS / \
