Re: [sqlite] Question about UTF8 encoding in SQLite version 2.8.13
Sorry to keep on about this, but I raised a ticket on Tuesday (number 981) with severity and priority of 1 (since this is a major issue for my projet) and I haven't heard anything back yet. Even if it is not going to be fixed, I really need to know, as then we can take some other action with this. Thanks, Liz. _ Express yourself with cool new emoticons http://www.msn.co.uk/specials/myemo
Re: [sqlite] Question about UTF8 encoding in SQLite version 2.8.13
Thanks for your reply, however, wcstombs uses the default code page rather that UTF8, which is where I was going wrong with using it originally. Unfortunately, it is unlikely that I will get approval to use libiconv as it is third-party software. How much effort is involved with converting to SQLite 3.x? I'm not sure if I can get approval to use that either, but if that's the only way I'm going to get it to work, then I may have to do it. Liz. Original Message Follows From: Cory Nelson <[EMAIL PROTECTED]> Reply-To: Cory Nelson <[EMAIL PROTECTED]> To: [EMAIL PROTECTED] Subject: Re: [sqlite] Question about UTF8 encoding in SQLite version 2.8.13 Date: Tue, 2 Nov 2004 08:41:25 -0800 Well, wcstombs uses WideCharToMultiByte() internally, with some more locality checks added in. Maybe you are using it wrong? If you cant get that to work, libiconv is great for converting charsets. Is there any reason you can't use sqlite 3.x? It has native unicode support. On Tue, 02 Nov 2004 15:50:59 +, Liz Steel <[EMAIL PROTECTED]> wrote: > Hello - I hope somebody can help me! > > I am using SQLite version 2.8.13 as a DLL with a windows C++ application. I > have the SQLITE_UTF8 macro defined. > > I have no problems adding and retrieving strings to and from the database - > I am using WideCharToMultiByte and MultiByteToWideChar to convert from > CString (Wide) to char * (Multibyte). > > (Previously I was using wcstombs and mbstowcs to convert, but this doesn't > support Greek and Russian characters, and I don't think it was actually > converting the strings properly.) > > However, when I call sqlite_open with a multibyte string, it doesn't seem to > work as I expect. > > To clarify: I have a database name with Swedish characters in, which are > converted to multibyte characters, however, the filename that is created > treats each of the characters separately, which then causes problems later. > As an example, the string "Ändrad" is converted to "Ändrad". > > If I use wcstombs to convert the filename string, this works OK for Swedish > characters, but then doesn't work for Greek characters. > > Does anyone have any ideas? > > Thanks, > > Liz. > > _ > Use MSN Messenger to send music and pics to your friends > http://www.msn.co.uk/messenger > > -- Cory Nelson http://www.int64.org _ Stay in touch with absent friends - get MSN Messenger http://www.msn.co.uk/messenger
[sqlite] Question about UTF8 encoding in SQLite version 2.8.13
Hello - I hope somebody can help me! I am using SQLite version 2.8.13 as a DLL with a windows C++ application. I have the SQLITE_UTF8 macro defined. I have no problems adding and retrieving strings to and from the database - I am using WideCharToMultiByte and MultiByteToWideChar to convert from CString (Wide) to char * (Multibyte). (Previously I was using wcstombs and mbstowcs to convert, but this doesn't support Greek and Russian characters, and I don't think it was actually converting the strings properly.) However, when I call sqlite_open with a multibyte string, it doesn't seem to work as I expect. To clarify: I have a database name with Swedish characters in, which are converted to multibyte characters, however, the filename that is created treats each of the characters separately, which then causes problems later. As an example, the string "Ändrad" is converted to "Ãndrad". If I use wcstombs to convert the filename string, this works OK for Swedish characters, but then doesn't work for Greek characters. Does anyone have any ideas? Thanks, Liz. _ Use MSN Messenger to send music and pics to your friends http://www.msn.co.uk/messenger
Re: [sqlite] Effectiveness of PRAGMA integrity_check;
Hello again, I'm not sure if you received my last email, so I'm sending it to the list in the hope that someone can help me. You say that I shouldn't get a corrupt database when I pull the power, but I am consistently getting this. I am using SQLite version 2.8.9 using the C++ interface running on Windows XP Home. Is there anything I can do to stop this happening? Thanks, Liz. Original Message Follows From: "D. Richard Hipp" <[EMAIL PROTECTED]> CC: [EMAIL PROTECTED] Subject: Re: [sqlite] Effectiveness of PRAGMA integrity_check; Date: Wed, 14 Apr 2004 10:50:28 -0400 Liz Steel wrote: I am trying to do a similar sort of thing with my database. The only way I've found to fairly reliably create a corrupt database file is to pull the battery out of my laptop whilst my application is accessing the database I've just tried it, and I get a code 11 (SQLITE_CORRUPT) returned from the PRAGMA integrity_check command. Is this correct behaviour? No, this is not correct. SQLite is suppose to survive an abrupt power loss with no loss of data. (Uncommitted transactions will be rolled back, but committed transactions should persist and be consistent.) I believe that SQLite does survive power loss without problems on Linux. However, I have received reports that the windows API function FlushFileBuffers() sometimes lies and does not really flush contents to the disk surface as it claims it does. This is just hearsay - I have not independently verified those reports. If FlushFileBuffers() does lie and a power loss occurred in the middle of a COMMIT, then database corruption is possible on windows. This is a bug in the OS and there is not anything SQLite (or any other database engine) can do about it. There was a bug in SQLite version 2.8.12 that could cause database corruption if a power loss occurred at a particularly inauspicious moment in the middle of a COMMIT. That problem was fixed with version 2.8.13. If you are seeing database corruption following power loss on Linux with SQLite version 2.8.13, please let us know about it right away. If you are seeing corruption on Windows, let us know there too - the problem might be the FlushFileBuffers() bug or it might be something else - either way we want to investigate. -- D. Richard Hipp -- [EMAIL PROTECTED] -- 704.948.4565 - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] _ Stay in touch with absent friends - get MSN Messenger http://www.msn.co.uk/messenger - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
RE: [sqlite] Effectiveness of PRAGMA integrity_check;
Hello!
I am trying to do a similar sort of thing with my database. The only way
I've found to fairly reliably create a corrupt database file is to pull the
battery out of my laptop whilst my application is accessing the database. I
haven't used the "PRAGMA integrity_check;" command, but I will try it now
and see if that detects my corrupt database. At the moment, I am selecting
every row from every table, but I can see this getting a bit slow when my
database gets bigger.
I've just tried it, and I get a code 11 (SQLITE_CORRUPT) returned from the
PRAGMA integrity_check command. Is this correct behaviour? Will I always get
this error returned? The website says something about it returning "ok" but
I didn't check this as I am using sqlite_exec.
I haven't managed to find anything on the website about using the journal
file that is created. Can anyone point me in the right direction to using
this file to re-create my database? Would I need to take a backup of the
database file before every transaction to use this?
Thanks,
Liz.
Original Message Follows
From: [EMAIL PROTECTED]
To: [EMAIL PROTECTED]
Subject: [sqlite] Effectiveness of PRAGMA integrity_check;
Date: Wed, 14 Apr 2004 15:48:57 +1000
G'day,
I'm trying to write some defensive code that is able to recover from
database corruption. The idea is that if a disk fails and a database
becomes corrupt it can be detected and synchronised from a backup copy.
To this end, I've just been trying to write a function that returns true
only when it is sure the database is ok. I use PRAGMA integrity check; and
compare the returned string with "ok". When I tried this with a few random
database changes, though, I had a hard time trying to get the corruption
to trigger. I did the following:
CREATE TABLE foo(bar);
INSERT INTO foo VALUES("bar");
I then went in with a text editor and started modifying the bar record. I
changed "bar" to "car", but the change was not detected. I started
modifying characters to the left and right of the "car" string, but still
no corruption. I was able to get corruption to be detected when I
truncated the file.
Can I take it from this behaviour that there isn't any checksum checking
going on apart from headers and the BTrees themselves? Will the
integrity_check at least guarantee me that I won't at some later stage get
an SQLITE_CORRUPT return?
Benjamin.
-
To unsubscribe, e-mail: [EMAIL PROTECTED]
For additional commands, e-mail: [EMAIL PROTECTED]
_
Tired of 56k? Get a FREE BT Broadband connection
http://www.msn.co.uk/specials/btbroadband
-
To unsubscribe, e-mail: [EMAIL PROTECTED]
For additional commands, e-mail: [EMAIL PROTECTED]
[sqlite] Case sensitivity using LIKE.
I have a problem that I'm hoping someone has already solved, or at least can point me in the right direction. I am using LIKE in a SELECT statement to search my database. Everything is fine when using standard English characters, and the select is not case sensitive, which is what I want However, if I use Swedish/German characters, for example Åå Ää Öö Üü, then the select is not case sensitive. I realise that this is a known issue with the current version of SQLite, but I am hoping that someone can point me in the right direction to solve this, either in the SQL statement itself, or in my code. (I am using Visual C++.) Thanks, Liz. _ Express yourself with cool new emoticons http://www.msn.co.uk/specials/myemo - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
[sqlite] Corrupt database problem.
I'm getting an error in my code when I perform a sqlite_finalize on a particular table. I have stepped through the code and no rows are returned, but why do I get the error here, rather than on sqlite_compile, or sqlite_open? I've looked at the database using the command line interface, and when I do a select on this table, I get quite a lot of rows, and then an error: SQL error: database disk image is malformed Can anyone shed any light on why I might get this error? What does it mean? Is there any way to repair the database? Thanks in advance, Liz. _ Stay in touch with absent friends - get MSN Messenger http://www.msn.co.uk/messenger - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Re: [sqlite] How do I get the last item in a list.
I've solved it! select * from (select * from hooverobject where timestamp < '2003/12/04 12:00:00:000' order by timestamp desc limit 100) order by timestamp asc limit 1 Liz. _ It's fast, it's easy and it's free. Get MSN Messenger today! http://www.msn.co.uk/messenger - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
[sqlite] How do I get the last item in a list.
I'm doing a select on a table as follows, and I want to get the last item in the list. How can I do this without having to step through all of the previous items? This may or may not return 100 rows since I cannot be sure of the size of the data. select * from tablename where timestamp < '2003/12/04 12:00:00:000' order by timestamp limit 100; Also, how do I access the archive of messages sent to this list now that it's moved from Yahoo? Thanks, Liz. _ Find a cheaper internet access deal - choose one to suit you. http://www.msn.co.uk/internetaccess - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Re: [sqlite] How do I get the last item in a list.
Nope - that just gets the one closest to the date I specified. Perhaps you meant to use "asc" instead of "desc", but that gets the oldest one in the list. What I'm trying to do is get the timestamp of 100th (or less if there are less than 100 previous items) previous item in the list. Thanks, Liz. Original Message Follows From: Gerhard Häring <[EMAIL PROTECTED]> To: [EMAIL PROTECTED] Subject: Re: [sqlite] How do I get the last item in a list. Date: Thu, 04 Dec 2003 15:58:41 +0100 Liz Steel wrote: I'm doing a select on a table as follows, and I want to get the last item in the list. How can I do this without having to step through all of the previous items? This may or may not return 100 rows since I cannot be sure of the size of the data. select * from tablename where timestamp < '2003/12/04 12:00:00:000' order by timestamp limit 100; select * from tablename where timestamp < '2003/12/04 12:00:00:000' order by timestamp desc limit 1; HTH, -- Gerhard - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] _ Use MSN Messenger to send music and pics to your friends http://www.msn.co.uk/messenger - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
