Neil Best wrote: > >>Anyone out there have any insight on how to define a regexp() function > >>for SQLite at run-time as described at > >>http://www.sqlite.org/lang_expr.html#regexp > > > > > > http://www.sqlite.org/capi3ref.html#sqlite3_create_function > > > > This would need to be done in the driver (db/drivers/sqlite), probably > > whenever a database is opened (db__driver_open_database, in db.c). > > > > As for implementation: regcomp/regexec should be available on all Unix > > systems, but you might need a separate library for Windows. > > > > Glynn, thanks for the reply. Programming at this level is not my strong > suit so it's difficult for me to gauge how much effort would be involved > in filling this gap. I have to wonder why this stub in SQLite has not > been filled in
Portability, perhaps. Windows systems won't have regexec(), while some Unix systems may have it in a separate library, requiring additional linker switches. There's also the choice of basic/extended/perl syntax. > but it seems like there are enough work-arounds, like > getting the results from SQLite and using your favorite scripting > language to do the regex filtering, such that the demand is simply not > there. I found a piece of code on the SQLite user list that claims to > meet this need[1] -- maybe someone would be interested in vetting this. It seems sound, although a version using POSIX REs would be preferable to PCREs, both for portability and for compatibility with other drivers. > I will write to the author and see what I can learn, especially > regarding his claim that linking to regex(7) doesn't really solve the > problem. I think that he's saying that using PCREs is bad for compatibility, as most other SQL implementations use POSIX REs. -- Glynn Clements <[EMAIL PROTECTED]> _______________________________________________ grassuser mailing list [email protected] http://grass.itc.it/mailman/listinfo/grassuser
