Re: [sqlite] Are SQLite offer dates with timezone support?
Tito Ciuro wrote: Hello, The only reference I see about timezone support in SQLite is in this example: Compute the date and time given a unix timestamp 1092941466, and compensate for your local timezone. SELECT datetime(1092941466, 'unixepoch', 'localtime'); I found this here: http://www.sqlite.org/cvstrac/wiki?p=DateAndTimeFunctions Where can I find more info? Timezones are enormously complicated, mostly because daylight saving time rules. Every locale does it a little bit differently. And the rules change from year to year. So, no, I am not going to fight that battle. Doing timezones correctly could easily double the size of the library. If you need timezones, link in a separate library that focuses on timezones. SQLite is going to stay focused on storing and retrieving data. -- D. Richard Hipp -- [EMAIL PROTECTED] -- 704.948.4565
[sqlite] Are SQLite offer dates with timezone support?
Hello, The only reference I see about timezone support in SQLite is in this example: Compute the date and time given a unix timestamp 1092941466, and compensate for your local timezone. SELECT datetime(1092941466, 'unixepoch', 'localtime'); I found this here: http://www.sqlite.org/cvstrac/wiki?p=DateAndTimeFunctions Where can I find more info? Thanks, -- Tito
Re: [sqlite] BLOBs and sqlite_exec
On Oct 16, 2004, at 2:04 AM, D. Richard Hipp wrote: Will Leshner wrote: Sorry if this is terribly obvious, but I'm assuming that, in SQLite3, we can't use the sqlite_exec convenience API to store BLOBs, right? Correct. The only way to insert a BLOB is using sqlite3_prepare() followed by sqlite3_bind_blob(). Thanks. That makes a lot of sense, actually.
Re: [sqlite] BLOBs and sqlite_exec
Daniel K wrote: I think there might be something, but I can't remember exactly. It might be: INSERT INTO tbl VALUES ( X'ABCD' ); where ABCD is the hex representation of the blob data. If you do a ".dump" command from the shell on a database that contains blobs and look at the output it might prove illuminating. Right, Dan. I forgot about that. You can insert a BLOB using sqlite3_exec() if you first encode the BLOB as a hexadecimal blob constant. -- D. Richard Hipp -- [EMAIL PROTECTED] -- 704.948.4565
Re: [sqlite] BLOBs and sqlite_exec
--- "D. Richard Hipp" <[EMAIL PROTECTED]> wrote: > Will Leshner wrote: > > Sorry if this is terribly obvious, but I'm > assuming that, in SQLite3, we > > can't use the sqlite_exec convenience API to store > BLOBs, right? > > I think there might be something, but I can't remember exactly. It might be: INSERT INTO tbl VALUES ( X'ABCD' ); where ABCD is the hex representation of the blob data. If you do a ".dump" command from the shell on a database that contains blobs and look at the output it might prove illuminating. Dan. ___ Do you Yahoo!? Declare Yourself - Register online to vote today! http://vote.yahoo.com
Re: [sqlite] BLOBs and sqlite_exec
Will Leshner wrote: Sorry if this is terribly obvious, but I'm assuming that, in SQLite3, we can't use the sqlite_exec convenience API to store BLOBs, right? Correct. The only way to insert a BLOB is using sqlite3_prepare() followed by sqlite3_bind_blob(). -- D. Richard Hipp -- [EMAIL PROTECTED] -- 704.948.4565
Re: [sqlite] multiple indexes.
Guillaume Fougnies wrote: Hello, I'd like to know if the management of multiple indexes on select statement is in the TODO list of SQLite? No. On joined request, this lack is a real performance killer. Example: select t1.id,t2.name from t1,t2 where t1.id IN(a00,b00, ,z99) and t1.t2id = t2.id; For now, SQLite use by default the wrong index and make a full join ignoring the 'IN' restriction. I need to force the index selection like this to gain a little speed: select t1.id,t2.name from t1,t2 where t1.id IN(a00,b00, ,z99) and +t1.t2id = t2.id; I think you are in error. In the situation about, SQLite will never chose to use an index on t1.t2id. It will always use the t1.id index (if there is one) for locating rows in table t1 and it will use the index on t2.id for locating rows in t2. This is true regardless of whether or not you attempt to disable the indices using the "+" sign. If you need help optimizing a query, post all relevant parts of the schema and the query you are working on and we will take a look. -- D. Richard Hipp -- [EMAIL PROTECTED] -- 704.948.4565
Re: [sqlite] LIKE, BETWEEN
Mike Ponomarenko wrote: In sqlite3 queries using LIKE and BETWEEN do not use existing indices. So for a schema like CREATE TABLE t (a integer, b char(40)); CREATE INDEX t_idx_0 ON t(a); CREATE INDEX t_idx_1 ON t(b); queries like "SELECT * FROM t WHERE a BETWEEN 1 AND 20"or "SELECT * FROM t WHERE b LIKE 'abc%'" end up doing a table scan. Just curious if there are any changes in the works to make queries such as above use available indices? No For BETWEEN: Integer 2, MoveGE, Next until > 20, etc. For LIKE: if one parameter is a string with a constant prefix, String8 'abc', MoveGE, Next until Function(LIKE) fails, etc. I realize that queries can be rewritten to make them more efficient (SELECT * FROM t WHERE a >= 1 AND a <= 20), etc., but it's not always feasible. I'd appreciate any thoughts on the matter. Thanks! Every effort is made to keep SQLite simple, small, and fast. Adding lots of code to do expression optimizations that could just as easily have been done by the user is contrary to those goals. -- D. Richard Hipp -- [EMAIL PROTECTED] -- 704.948.4565
Re: [sqlite] SQLITE_BUSY returned without busy handler called
Kevin Schmeichel wrote: By examining the code, it can be seen that there are many places where SQLITE_BUSY is returned (from an API function) without the busy handler being called. Anyone know if there is any reason for this? I would have thought that the busy handler would be called *every* time that the db is busy. There are circumstances where waiting and retrying a lock will not help. In those cases, there is no point in calling the busy handler. The busy handler is also not called when failing to obtain a RESERVED lock unless the library is recompiled with -DSQLITE_BUSY_RESERVED_LOCK=1. Not waiting on a reserved lock helps to resolve locking conflicts faster. -- D. Richard Hipp -- [EMAIL PROTECTED] -- 704.948.4565
Re: [sqlite] Support for ODBC?
Le vendredi 15 Octobre 2004 09:23, Eric Bohlman a écrit : > R S wrote: > > Can an application access data from SQLite via ODBC? Didn't see > > documentation on the same. > > If you have an ODBC driver for SQLite, yes. The "SQLite Wrappers" page > of the wiki mentions "ODBC driver for SQLite. > http://www.ch-werner.de/sqliteodbc/";. I don't know anything about it, > but check out the URL. > The SQLite ODBC driver has been written by Christian Werner and make it possible to access a SQLite database file from applications which are ODBC compatible. I use it with OpenOffice.org in linux and windows. You can find here a how-to about that (http://documentation.openoffice.org/HOW_TO/data_source/SQLite.sxw) I hope this will help you. Yves
Re: [sqlite] GUI ?
Take a look at the excellent QuickLite Cocoa wrapper. http://www.webbotech.com/ It has a few sample applications, including one called "SQLIteManagerX" which may be sufficient for your needs. Demitri --- On Oct 15, 2004, at 8:53 PM, Richard wrote: wondering if there are any Mac OS X GUI front-end apps, that will work with SQlite ? Thanks - Richard
