On 18 Nov 2009, at 6:05pm, Roger Binns wrote: > Tim Romano wrote: >> This would be a convenient function to have. Are there technical >> issues/obstacles? > > In general for all these feature requests for more functions there is no > need for them to be added to the SQLite core. There is a very simple API > and extension mechanism whereby you can add your own functions that do > exactly what you want.
I googled, and there doesn't seem to be a page which describes the abilities and limitations the extension system has. I'd like to check, then, with someone who understands how to write extensions. (A) Is it possible to define a new datatypen ? If the data itself was really stored in a BLOB, that would be okay, but I wouldn't want my users to know that, I'd want them to use this new datatype when they created columns. (B) If not, then if I needed to store some additional information for every TEXT field, could I do that ? If it was necessary to store it in a different table in the same database, e.g. to define a new table with tablename fieldname rowid columnname language that would be acceptable though very slow, but can an extension do that sort of thing ? And can a routine of an extension be automatically called whenever any row, column or table in the database is created/deleted ? (C) Is it possible to put a note inside a database file so that if a database was opened without a particular extension being loaded, an error would occur ? For example a SQLITE error code, with error text something like "This database cannot be used without version 1.1 or higher of the extension 'complex numbers' being loaded." ? Simon. _______________________________________________ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
