Re: [sqlite] Cause of "disk I/O errors"

2011-01-30 Thread Max Vlasov
On Mon, Jan 31, 2011 at 4:25 AM, GHCS Software wrote: > > So it seems it must be something about their particular machine > environment, but what? I'm sure that nobody is running out of disk space > these days. Any ideas on where to look or what to suggest to them that > they can do? > > Maybe ant

Re: [sqlite] WAL for single user database on NFS and Solaris

2011-01-30 Thread Ginn Chen
On Jan 31, 2011, at 12:26 PM, Dan Kennedy wrote: > If you set "PRAGMA locking_mode=EXCLUSIVE" before reading or > writing the WAL-mode database it might work. > > http://www.sqlite.org/wal.html#noshm > > Dan. Thanks, with sqlite 3.7,.4, it works if I run "PRAGMA locking_mode=EXCLUSIVE" as t

Re: [sqlite] WAL for single user database on NFS and Solaris

2011-01-30 Thread Nicolas Williams
On Sun, Jan 30, 2011 at 11:06:34AM +0800, Ginn Chen wrote: > I think a single process accessing a single Sqlite database at a time over > NFS is supposed to be fine. > > But it is not working on Solaris. > On Solaris, man page of mmap() has > > EAGAINThe file to be mapped is already

Re: [sqlite] WAL for single user database on NFS and Solaris

2011-01-30 Thread Dan Kennedy
On 01/30/2011 10:06 AM, Ginn Chen wrote: > I think a single process accessing a single Sqlite database at a time over > NFS is supposed to be fine. > > But it is not working on Solaris. > On Solaris, man page of mmap() has > > EAGAINThe file to be mapped is already locked using >

Re: [sqlite] Cause of "disk I/O errors"

2011-01-30 Thread Jay A. Kreibich
On Sun, Jan 30, 2011 at 08:25:48PM -0500, GHCS Software scratched on the wall: > Are there any common reasons for encountering a "disk I/O error" (code > 10) when creating records in an SQLite database on a Windows PC? Check to be sure the application has permission to create new files in the

Re: [sqlite] Cause of "disk I/O errors"

2011-01-30 Thread Simon Slavin
On 31 Jan 2011, at 1:25am, GHCS Software wrote: > Are there any common reasons for encountering a "disk I/O error" (code > 10) when creating records in an SQLite database on a Windows PC? [snip] > > So it seems it must be something about their particular machine > environment, but what? File

[sqlite] Cause of "disk I/O errors"

2011-01-30 Thread GHCS Software
Are there any common reasons for encountering a "disk I/O error" (code 10) when creating records in an SQLite database on a Windows PC? My product uses V3.6.23.1 and I did not have extended error codes turned on in my releases up to now. The problem in reproducing this is that the users can be

Re: [sqlite] slow select from table with data blob

2011-01-30 Thread Rael Bauer
@Jay: Thanks for the official information. >You'll see the slow down anytime you access anything "past" the BLOB. >To avoid that, put the BLOBs at the end of the rows and avoid "SELECT *" style >queries. Yes this is exactly what I found.. The problem with putting them at the end of the table i

Re: [sqlite] SELECT difference between TABLE and VIEW

2011-01-30 Thread Simon Slavin
On 30 Jan 2011, at 11:34am, Lapo Luchini wrote: > Column headers are different if obtained from a table or a view: Yep. The column headers are defined very precisely for columns retrieved directly from a table. For anything else, they're not defined very clearly. Try looking at the column h

Re: [sqlite] SELECT difference between TABLE and VIEW

2011-01-30 Thread Igor Tandetnik
Lapo Luchini wrote: > Column headers are different if obtained from a table or a view: >From http://www.sqlite.org/c3ref/column_name.html: The name of a result column is the value of the "AS" clause for that column, if there is an AS clause. If there is no AS clause then the name of the column

Re: [sqlite] LAST() function not supported

2011-01-30 Thread Nicolas Williams
On Sat, Jan 29, 2011 at 01:06:07PM -0800, Marian Cascaval wrote: > On Sat, January 29, 2011, Nicolas Williams wrote: > > If there's enough indices to satisfy all the ORDER BY expressions then > > how could a "last()" function do any better? For that matter, if there > > aren't enough indices to sa

Re: [sqlite] slow select from table with data blob

2011-01-30 Thread Eduardo
On Sat, 29 Jan 2011 15:07:47 -0800 (PST) Rael Bauer wrote: > It seemed strange that a simple "select * from table" that I was > doing was so slow. The table contained about 20 columns (fields) and > 300 rows. The select took about 1.5 seconds. (using SQLite Expert). > > So my questions: > Is this

[sqlite] SELECT difference between TABLE and VIEW

2011-01-30 Thread Lapo Luchini
Column headers are different if obtained from a table or a view: % sqlite3 a SQLite version 3.7.4 Enter ".help" for instructions Enter SQL statements terminated with a ";" sqlite> CREATE TABLE a (a); sqlite> CREATE VIEW b AS SELECT * FROM a; sqlite> INSERT INTO a VALUES ('foo'); sqlite> .header on

Re: [sqlite] slow select from table with data blob

2011-01-30 Thread Jean-Christophe Deschamps
>It seemed strange that a simple "select * from table" that I was doing >was so slow. The table contained about 20 columns (fields) and 300 >rows. The select took about 1.5 seconds. (using SQLite Expert). Does the run time settle at 1.5 s after a few runs or is that a first-run time ? As an a