Re: [sqlite] Expected behavior for begin exclusive?/database locked?

2009-06-05 Thread Rosemary Alles
I established re-try logic to get this to work. :( On Jun 5, 2009, at 7:08 PM, Rosemary Alles wrote: > > I have several (identical processors) accessing a sqlite3 database > over NFS. I have a busy handler (see below) and use "begin exclusive" > > Periodically I get

[sqlite] Expected behavior for begin exclusive?/database locked?

2009-06-05 Thread Rosemary Alles
I have several (identical processors) accessing a sqlite3 database over NFS. I have a busy handler (see below) and use "begin exclusive" Periodically I get the following error from from sqlite3: Function:artd_sql_exec_stmt error in stmt:begin exclusive against database:/wise/fops/ref/artid/l

Re: [sqlite] Re-try logic on SQLITE_BUSY/deadlocked?

2009-05-22 Thread Rosemary Alles
Thanks Simon. I have been leaning that way too - considering switching. -rosemary. On May 22, 2009, at 5:55 PM, Simon Slavin wrote: > > On 23 May 2009, at 12:10am, Rosemary Alles wrote: > >> Multiple machines with multiple cpus. [snip] > >> The total size of >> c

Re: [sqlite] Re-try logic on SQLITE_BUSY/deadlocked?

2009-05-22 Thread Rosemary Alles
will be sufficient? -rosemary. On May 22, 2009, at 4:10 PM, Rosemary Alles wrote: > Dear Olaf, > > On May 22, 2009, at 3:21 PM, Olaf Schmidt wrote: > >> >> "Rosemary Alles" schrieb im >> Newsbeitrag >> news:f113017d-8851-476d-8e36-56b2c4165...@ipac.calte

Re: [sqlite] Re-try logic on SQLITE_BUSY/deadlocked?

2009-05-22 Thread Rosemary Alles
Using busy_timeout in itself won't do the job. From what I'm gathering I need to rollback the transaction that returned BUSY, reset the statement and retry once the database is not BUSY anymore?I probably also don't want the default BEGIN. I probably want either IMMEDIATE or EXCLUSIVE. Add

Re: [sqlite] Re-try logic on SQLITE_BUSY/deadlocked?

2009-05-22 Thread Rosemary Alles
Dear Olaf, On May 22, 2009, at 3:21 PM, Olaf Schmidt wrote: > > "Rosemary Alles" schrieb im > Newsbeitrag > news:f113017d-8851-476d-8e36-56b2c4165...@ipac.caltech.edu... > >> I have a database (simple schema) with two tables on which I >> p

[sqlite] Re-try logic on SQLITE_BUSY/deadlocked?

2009-05-22 Thread Rosemary Alles
Hullo all, Does anyone have solid code examples (in C/C++) or pseudo code of how to establish re-try code/logic successfully? I have a database (simple schema) with two tables on which I perform "concurrent" udpates over NFS (yes, terrible I know - but it's what we have). Eventually, I get

Re: [sqlite] Optimizing concurrency with sql query - locks?

2009-05-06 Thread Rosemary Alles
Many thanks to all of you for your responses. Helped a great deal. I think I'm experiencing a "duh" moment. :) -rosemary. On May 6, 2009, at 10:34 AM, Olaf Schmidt wrote: > > "Rosemary Alles" schrieb im > Newsbeitrag news:AF79A266-B697-4924- > b304-2b1f

[sqlite] Optimizing concurrency with sql query - locks?

2009-05-05 Thread Rosemary Alles
Hullo all, Run on a single processor, the following query is quite fast: // Select Statement sprintf(sql_statements, "select lp.%s, lp.%s, lp.%s, lp.%s, pb.%s from %s lp, %s pb " "where lp.%s > ? and lp.%s=pb.%s " "order by lp.%s, lp.%s, pb.%s",

[sqlite] Bizarre sqlite3 idiocyncrasy

2009-04-22 Thread Rosemary Alles
Hullo all, Including the following in my c-program: sql_rc = sqlite3_open_v2(database_name, &sql_db, SQLITE_OPEN_READONLY, NULL); if (sql_rc != SQLITE_OK) { fprintf(stderr, "Function:%s c

Re: [sqlite] Select statements in the context of transactions.

2009-04-07 Thread Rosemary Alles
Thanks Puneet. Those suggestions really help. -rosemary. On Apr 7, 2009, at 5:52 PM, P Kishor wrote: > On Tue, Apr 7, 2009 at 5:18 PM, Rosemary Alles > wrote: >> Puneet, >> >> As you suggested I have supplied a brief background re: the problem: >> >> Ba

Re: [sqlite] Select statements in the context of transactions.

2009-04-07 Thread Rosemary Alles
a WITH INDEX source_id_index_lp_tbl Many thanks, rosemary. On Apr 7, 2009, at 1:57 PM, P Kishor wrote: > On Tue, Apr 7, 2009 at 3:45 PM, Rosemary Alles > wrote: >> Hullo Puneet, >> >> Many thanks for your response. >> >> My understanding of a sqlite3 "tra

Re: [sqlite] Select statements in the context of transactions.

2009-04-07 Thread Rosemary Alles
s there no difference in behavior between a SINGLE select and several of them within the context of transaction? And yes, each of the many SELECTS have a different WHERE clause. -rosemary. On Apr 7, 2009, at 12:38 PM, P Kishor wrote: > On Tue, Apr 7, 2009 at 2:36 PM, Rosemary Alles >

Re: [sqlite] Select statements in the context of transactions.

2009-04-07 Thread Rosemary Alles
p. In what context does one parse the results? Do we not have synchronizing issue here? Thanks again, rosemary On Apr 6, 2009, at 8:03 PM, Igor Tandetnik wrote: > "Rosemary Alles" wrote > in message news:20a6b796-613b-4f5d-bfca-359d6b9fa...@ipac.caltech.edu >> I want to s

[sqlite] Select statements in the context of transactions.

2009-04-06 Thread Rosemary Alles
I want to speed up my app. Can I run SELECT statements within the context of a transaction. If so, how does one handle the query results? I would assume this cannot be done with sql_prepare, sql_bind, sql_step? Would I *have* to use sql_exec - such that a callback can be specified to handle

[sqlite] sqlite3 query optimization question

2009-04-06 Thread Rosemary Alles
Hullo everyone, I'm relatively new to sqlite. I have an optimization problem regarding an sql query. Background: I have a database with two tables one with -say- 12k rows of data, and the other with more. The first table (lets calls it A) has the following columns: source_id, x_pos, y_pos,