Dear Mr Hipp, That's quite a privilege to get this answer from SQLite's creator himself ! Thanks for the clarification, I guess I didn't switch my brain to formal logic when I read this part of the docs...
Have a nice day, Jonathan -----Original Message----- From: sqlite-users [mailto:[email protected]] On Behalf Of Richard Hipp Sent: vendredi 3 février 2017 05:05 To: SQLite mailing list Subject: Re: [sqlite] WAL and consistency On 2/2/17, Rossel, Jonathan <[email protected]> wrote: > Hi, > > Let me first congratulate you for the awesome product that SQLite is! > I just need a clarification with respect to a comment given in the > docs > (http://sqlite.org/pragma.html#pragma_synchronous): > > "With synchronous=FULL in WAL mode, an additional sync operation of > the WAL file happens after each transaction commit. The extra WAL sync > following each transaction help ensure that transactions are durable > across a power loss, but they do not aid in preserving consistency." Transactions are fully consistent with our without the extra syncs. Since transactions are already fully consistent without the extra syncs, adding the extra syncs adds no additional consistency. > > I don't understand the last bit about consistency preservation and > couldn't find more clues on that subject in the docs. Why would consistency > be lost ? > Is SQLite in WAL mode not ACID when synchronous=FULL ? What kind of > damage can we expect in case of power loss (assuming the disk performs > the syncs as > supposed) ? > > Thanks in advance ! > > Jonathan > > > > ********************************************************************** > ********* This e-mail message is intended only for the addressee(s) > and contains information which may be confidential. If you are not the > intended recipient please do not read, save, forward, disclose or copy > the contents of this e-mail. If this e-mail has been sent to you in > error, please delete this e-mail and any copies or links to this > e-mail completely and immediately from your system. We also like to > inform you that communication via e-mail over the Internet is insecure > because third parties may have the possibility to access and > manipulate e-mails. > > Any views expressed in this message are those of the individual > sender, except where the sender specifically states them to be the > views of The Swatch Group Ltd. > ********************************************************************** > ********* _______________________________________________ > sqlite-users mailing list > [email protected] > http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users > -- D. Richard Hipp [email protected] _______________________________________________ sqlite-users mailing list [email protected] http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users ******************************************************************************* This e-mail message is intended only for the addressee(s) and contains information which may be confidential. If you are not the intended recipient please do not read, save, forward, disclose or copy the contents of this e-mail. If this e-mail has been sent to you in error, please delete this e-mail and any copies or links to this e-mail completely and immediately from your system. We also like to inform you that communication via e-mail over the Internet is insecure because third parties may have the possibility to access and manipulate e-mails. Any views expressed in this message are those of the individual sender, except where the sender specifically states them to be the views of The Swatch Group Ltd. ******************************************************************************* _______________________________________________ sqlite-users mailing list [email protected] http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users
