Re: [sqlite] Connection philosophy

2013-01-23 Thread Ward Willats
On Jan 22, 2013, at 8:18 PM, Keith Medcalf wrote: > I presume that you are using some kind of input-driven or event driven > application which may get a request to process a query "in the middle" of > your update transaction. That is correct. > One of the advantages

Re: [sqlite] Connection philosophy

2013-01-22 Thread Keith Medcalf
On Tuesday, 22 January, 2013 19:14 MST, Ward Willats wrote: > On Jan 22, 2013, at 5:54 PM, Keith Medcalf wrote: >> In my case, I only have one writer (I think!) during the big transaction, >> so a long-lived, singleton connection or WAL should

Re: [sqlite] Connection philosophy

2013-01-22 Thread Keith Medcalf
On Tuesday, 22 January, 2013 19:14 MST, Ward Willats wrote: > On Jan 22, 2013, at 5:54 PM, Keith Medcalf wrote: >> I prefer the long-lived approach. Continuously re-initialization of the >> connection on open, the need to re-read pages into the

Re: [sqlite] Connection philosophy

2013-01-22 Thread Ward Willats
On Jan 22, 2013, at 5:54 PM, Keith Medcalf wrote: > I prefer the long-lived approach. Continuously re-initialization of the > connection on open, the need to re-read pages into the page cache > repetitively, and the subsequent discard of a nicely loaded page-cache on >

Re: [sqlite] Connection philosophy

2013-01-22 Thread Keith Medcalf
> All is well, EXCEPT, I have ONE big, long transaction that collects and > stores a lot of data from some sensors. If this data is big enough, it > will eventually cause that connection to obtain an exclusive lock on the > DB. Now if the data collection code subsequently calls any subroutine

Re: [sqlite] Connection philosophy

2013-01-22 Thread Ward Willats
On Jan 22, 2013, at 10:07 AM, Simon Slavin wrote: > Change the code used in your one big thread so that it counts the number if > INSERT/UPDATEs it does and changes transactions and does a little pause after > every thousand ops. Or hundred. Whatever. > Cool idea,

Re: [sqlite] Connection philosophy

2013-01-22 Thread Simon Slavin
On 22 Jan 2013, at 5:39pm, Ward Willats wrote: > I have a bunch of home-grown C++ wrappers for Sqlite and when my app needs to > use the DB, most routines just instance one of these DB wrapper objects on > the stack and go for it. The constructor creates a new DB

[sqlite] Connection philosophy

2013-01-22 Thread Ward Willats
Hello. Just wondering what the group opinion is on something. I have a bunch of home-grown C++ wrappers for Sqlite and when my app needs to use the DB, most routines just instance one of these DB wrapper objects on the stack and go for it. The constructor creates a new DB connection, which is