Re: [sqlite] Extra functions - New Project?
Mikey C wrote: StdDev Variance When implementing these, make sure *not* to use the "textbook" one-pass formula (mean of the squares - square of the mean); it simply doesn't work properly in floating point (you can find yourself subtracting one large number from another and losing most of your precision). I believe many versions of Excel made that mistake. There are some numerically stable one-pass algorithms for computing variance; search for them if you don't want to make two passes.
Re: [sqlite] Extra functions - New Project?
Heh. You learn something new everyday.
If it behaves the same, then it is!
I guess I need to look at the docs again!
thanks...
-alex
On May 25, 2006, at 3:56 PM, Griggs, Donald wrote:
Regarding: A non-standard SQL function I like, and don't think I've
seen
anywhere but an Aspentech product is SUBSTRING.
Alex,
Is the second option ("positional") not identical to the existing
"substr"
function?
E.g. for
strFoo = 'abcdefgh';
Instead of
substring(strFoo from 1 for 4) returning 'abcd'
Use
substr(strFoo,1,4)
http://sqlite.org/lang_expr.html
Donald Griggs
Opinions are not necessarily those of Misys Healthcare Systems nor
its board
of directors.
RE: [sqlite] Extra functions - New Project?
Regarding: A non-standard SQL function I like, and don't think I've seen
anywhere but an Aspentech product is SUBSTRING.
Alex,
Is the second option ("positional") not identical to the existing "substr"
function?
E.g. for
strFoo = 'abcdefgh';
Instead of
substring(strFoo from 1 for 4) returning 'abcd'
Use
substr(strFoo,1,4)
http://sqlite.org/lang_expr.html
Donald Griggs
Opinions are not necessarily those of Misys Healthcare Systems nor its board
of directors.
Re: [sqlite] Extra functions - New Project?
I tend to use SQLLite via the command line, feeding in queries from an external file. A non-standard SQL function I like, and don't think I've seen anywhere but an Aspentech product is SUBSTRING. It works in two ways 1 - Delimited strFoo = 'abcd efgh'; substring(1 of strFoo between ' ') = 'abcd' strFoo = 'abcd,efgh'; substring(2 of strFoo between ',') = 'efgh' 2 - Positional strFoo = 'abcdefgh'; substring(strFoo from 1 for 4) = 'abcd' substring(strFoo from 4 for 4) = 'defg' I'd be interested in seeing that. If I can be of help, feel free to ask. -alex On May 25, 2006, at 7:35 AM, Mikey C wrote: With some assistance I intend to implement pretty much all the SQL Server 2000 arithmetic and string functions into SQLite 3 codebase as well as a few others, such as aggregates for StdDev and Variance. I will then release the source under the same license as SQLite itself. If anyone has any comments or suggestions, please let me know. -- View this message in context: http://www.nabble.com/Extra+functions +-+New+Project--t1674436.html#a4559014 Sent from the SQLite forum at Nabble.com.
Re: [sqlite] Extra functions - New Project?
These are the functions that I tend to have implemented: Numeric Functions: Sqrt Floor Ceiling Sign Pi - constant function 3.141.. ACos ASin ATan Atn2 Cos Cot Degrees Exp Log Log10 Power Radians Sin Square Tan String Functions: Charindex Patindex Left Right LTrim RTrim Trim Replicate Reverse Replace Difference - numeric diff in Soundex values using built in soundex function. Aggregate Functions: StdDev Variance Median - Possibly a more flexible function Percentile where 0.5 is the Median Mode - Most frequently occuring value -- View this message in context: http://www.nabble.com/Extra+functions+-+New+Project--t1674436.html#a4563121 Sent from the SQLite forum at Nabble.com.
Re: [sqlite] Extra functions - New Project?
Good idea. I can help with code and ideas. Contact me at [EMAIL PROTECTED] Mikey C wrote: With some assistance I intend to implement pretty much all the SQL Server 2000 arithmetic and string functions into SQLite 3 codebase as well as a few others, such as aggregates for StdDev and Variance. I will then release the source under the same license as SQLite itself. If anyone has any comments or suggestions, please let me know. -- View this message in context: http://www.nabble.com/Extra+functions+-+New+Project--t1674436.html#a4559014 Sent from the SQLite forum at Nabble.com.
Re: [sqlite] SQLite under mono
Thanks for you help, this is exactly what I was trying to find. Regards, Ben Mikey C wrote: http://www.mono-project.com/SQL_Lite -- View this message in context: http://www.nabble.com/SQLite+under+mono-t1680769.html#a4558894 Sent from the SQLite forum at Nabble.com.
Re: [sqlite] Extra functions - New Project?
With some assistance I intend to implement pretty much all the SQL Server 2000 arithmetic and string functions into SQLite 3 codebase as well as a few others, such as aggregates for StdDev and Variance. I will then release the source under the same license as SQLite itself. If anyone has any comments or suggestions, please let me know. -- View this message in context: http://www.nabble.com/Extra+functions+-+New+Project--t1674436.html#a4559014 Sent from the SQLite forum at Nabble.com.
Re: [sqlite] SQLite under mono
http://www.mono-project.com/SQL_Lite -- View this message in context: http://www.nabble.com/SQLite+under+mono-t1680769.html#a4558894 Sent from the SQLite forum at Nabble.com.
[sqlite] SQLite under mono
Dear SQLite, I have need to access SQLite using Mono on Linux. Probably using C# .NET code either natively accessing an sqlite3 database, or calling libsqlite3.so.0. I can't see any native .NET drivers for sqlite3, which is where I would like to go. Do any members know if such a lib does exist? If not, any body got any experience of binding mono to the native Linux sqlite3 lib? Thanks, Ben
