Re: [sqlite] How many concurrent sqlite3 connections are allowed?

2019-03-29 Thread Simon Slavin
On 29 Mar 2019, at 11:29pm, Peng Yu wrote: > I have many concurrent sqlite3 connections from many python scripts. I am not > sure this causes some deadlock condition, but my scripts do not show any > progress after some initial progress. There is no limit on how many connections can talk to

[sqlite] How many concurrent sqlite3 connections are allowed?

2019-03-29 Thread Peng Yu
Hi, I have many concurrent sqlite3 connections from many python scripts. I am not sure this causes some deadlock condition, but my scripts do not show any progress after some initial progress. Is it that somehow many open connections can cause problems? Thanks. -- Regards, Peng

Re: [sqlite] Row locking sqlite3

2019-03-29 Thread Thomas Kurz
I apologize that I am currently unable to reproduce the problem. The files I have just tested at home (same schema as the one I had in the office this week) behave as expected (i.e. no difference with or without transaction). I will try again in the office next week. If I can find the database

Re: [sqlite] Row locking sqlite3

2019-03-29 Thread Dan Kennedy
On 28/3/62 01:04, Thomas Kurz wrote: I wonder whether SQLite is treating each DELETE as a single transaction. Could you try wrapping the main delete in BEGIN ... END and see whether that speeds up the cascaded DELETE ? Would you be able to find timings (either in your code or in the

Re: [sqlite] UPSERT with multiple constraints

2019-03-29 Thread Thomas Kurz
You are right. This is indeed a situation that I didn't have in mind. I will rethink the data design. Thank you very much for this comment and also to all others which gave me valuable ideas on how to handle my conflict. - Original Message - From: James K. Lowden To:

Re: [sqlite] UPSERT with multiple constraints

2019-03-29 Thread James K. Lowden
On Wed, 27 Mar 2019 23:59:47 +0100 Thomas Kurz wrote: > Sure. I have a table of items. Each item has a type, a name, and > properties A, B, C (and some more, but they're not relevant here). > > I want to enforce ... UNIQUE (type, name). ... > Furthermore, items of a certain type that have

Re: [sqlite] WAL grows without bounds, short concurrent writes & reads

2019-03-29 Thread Joshua Wise
Awww sadness. Regardless, thanks for the update. > On Mar 29, 2019, at 11:07 AM, Richard Hipp wrote: > > On 3/29/19, Joshua Wise wrote: >> Dan, are there any plans to merge the wal2 branch into the trunk? > > No, not at this time. > > > -- > D. Richard Hipp > d...@sqlite.org >

Re: [sqlite] WAL grows without bounds, short concurrent writes & reads

2019-03-29 Thread Richard Hipp
On 3/29/19, Joshua Wise wrote: > Dan, are there any plans to merge the wal2 branch into the trunk? No, not at this time. -- D. Richard Hipp d...@sqlite.org ___ sqlite-users mailing list sqlite-users@mailinglists.sqlite.org

Re: [sqlite] WAL grows without bounds, short concurrent writes & reads

2019-03-29 Thread Joshua Wise
Dan, are there any plans to merge the wal2 branch into the trunk? > On Mar 29, 2019, at 7:10 AM, Dan Kennedy wrote: > > > There's code here, if you want to experiment with it: > > https://sqlite.org/src/timeline?r=wal2 > > Docs: > > https://sqlite.org/src/artifact/a807405a05e19a49 > >

Re: [sqlite] is this possible

2019-03-29 Thread Simon Slavin
On 29 Mar 2019, at 1:55pm, Dan Kennedy wrote: > The error doesn't occur unless you actually query the view though, correct? My theory on SQLite was that the VIEW definition was only syntax-checked and not compiled in any way. So you could do CREATE VIEW v as select * from t ORDER BY a;

Re: [sqlite] is this possible

2019-03-29 Thread Igor Tandetnik
On 3/29/2019 9:55 AM, Dan Kennedy wrote: On 29/3/62 03:00, Igor Tandetnik wrote: On 3/28/2019 3:21 PM, Mark Wagner wrote: Imagine I have these two tables and one view defining a join. CREATE TABLE t (foo); CREATE TABLE s (bar); CREATE VIEW v as select * from t join s on (foo = q);

Re: [sqlite] is this possible

2019-03-29 Thread Dan Kennedy
On 29/3/62 03:00, Igor Tandetnik wrote: On 3/28/2019 3:21 PM, Mark Wagner wrote: Imagine I have these two tables and one view defining a join. CREATE TABLE t (foo); CREATE TABLE s (bar); CREATE VIEW v as select * from t join s on (foo = q); Surprisingly, this last statement succeeds. But if

Re: [sqlite] Query Regression IN and Virtual Tables

2019-03-29 Thread Dan Kennedy
On 29/3/62 14:32, Hick Gunter wrote: When upgrading from 3.7.14.1 to 3.24 I noticed the following problem Given a virtual table like CREATE VIRTUAL TABLE vt ( key1 INTEGER, key2 INTEGER, key3 INTEGER, attr1 INTEGER,...); whose xBestIndex function simulates (in unsupported syntax) CREATE

Re: [sqlite] WAL grows without bounds, short concurrent writes & reads

2019-03-29 Thread Dan Kennedy
There's code here, if you want to experiment with it:   https://sqlite.org/src/timeline?r=wal2 Docs:   https://sqlite.org/src/artifact/a807405a05e19a49 Dan. On 29/3/62 01:33, Florian Uekermann wrote: Hi, A very simple reproducer bash script using the sqlite3 CLI is appended at the end.

[sqlite] Query Regression IN and Virtual Tables

2019-03-29 Thread Hick Gunter
When upgrading from 3.7.14.1 to 3.24 I noticed the following problem Given a virtual table like CREATE VIRTUAL TABLE vt ( key1 INTEGER, key2 INTEGER, key3 INTEGER, attr1 INTEGER,...); whose xBestIndex function simulates (in unsupported syntax) CREATE VIRTUAL INDEX vt_key ON vt (key1, key2,