Perfect - thank you both.. On Thu, Jul 14, 2011 at 12:15 PM, Simon Slavin <slav...@bigfraud.org> wrote:
> > On 13 Jul 2011, at 1:13pm, Amit Chaudhuri wrote: > > > I have situation where a column may contain prices (REAL) or a string > > meaning "no price for this, sorry." I can handle this in application code > > but was wondering if I am overlooking a Sqlite feature which might do the > > same out of the box: perhaps a TYPE( ) or an IsText( ) function..? > > There is a 'typeof'. But you didn't know the proper way to do it. What > you do is set up the column to be a number format (real or integer, however > you hold your prices) and use NULL when you don't have a price. Then you > can very quickly and easily check for a NULL with > > typeof(X) = 'null' > nullif(X,Y) > > or convert it to your 'no price for this' string with > > ifnull(X,'No price for this, Sorry.') > > In fact this is what NULL means in SQL: something like 'data missing' or > 'value unknown'. So it is exactly what you really want. For more details > see > > <http://www.sqlite.org/lang_corefunc.html> > > For how to do calculations on numbers that might be NULL, see > > <http://www.sqlite.org/lang_aggfunc.html> > > For more details than you need don't bother seeing > > <http://www.sqlite.org/nulls.html> > > Simon. > _______________________________________________ > sqlite-users mailing list > sqlite-users@sqlite.org > http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users > _______________________________________________ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
