Thank you for the quick reply. After reading your reply and grepping around for more examples containing sqlite3_type_value I see now the documentation gives the impression that return types only apply to sqlite3_value_numeric_type(). Had I clicked randomly on the link to https://sqlite.org/c3ref/c_blob.html in that unrelated paragraph I would have seen this wonderful exhibit:
#define SQLITE_INTEGER 1 #define SQLITE_FLOAT 2 #define SQLITE_BLOB 4 #define SQLITE_NULL 5 #ifdef SQLITE_TEXT # undef SQLITE_TEXT #else # define SQLITE_TEXT 3 #endif #define SQLITE3_TEXT 3 sqlite3_value_type() definitely deserves at least one document sentence within https://sqlite.org/c3ref/value_blob.html containing the link to https://sqlite.org/c3ref/c_blob.html On Fri, Jun 30, 2017 at 10:26 AM, Richard Hipp <d...@sqlite.org> wrote: > On 6/30/17, petern <peter.nichvolo...@gmail.com> wrote: > > Is this the recommended way for any argument type? > > > > zCol = (const char*)sqlite3_value_text(argv[i]); > > if( 0==zCol ) return; > > No. What you have above detects out-of-memory errors when trying to > convert an argument in some non-TEXT type in to TEXT, or when > converting a UTF-16 text string into the requested UTF-8. > > To get the argument type, use: > > sqlite3_value_type(argv[i]) > > > > > > Docs say protected_sqlite3_value can represent NULL but how is not > > explained anywhere. > > > > https://www.sqlite.org/c3ref/value_blob.html > > https://www.sqlite.org/c3ref/value.html > > > > To detect NULL arguments is it normal to test with sqlite3_value_text on > > every type of argument including BLOB, double, int,..? Or, are there > some > > special sentinel values {MAX_INT,DBL_MAX,...} for those other types? > > > > I'd be happily corrected if wrong, but it seems C API NULL value > > representation is not explained anywhere in the SQLite docs. The short > > answer to this question would make a well needed addition to one of those > > doc pages. > > _______________________________________________ > > sqlite-users mailing list > > sqlite-users@mailinglists.sqlite.org > > http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users > > > > > -- > D. Richard Hipp > d...@sqlite.org > _______________________________________________ > sqlite-users mailing list > sqlite-users@mailinglists.sqlite.org > http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users > _______________________________________________ sqlite-users mailing list sqlite-users@mailinglists.sqlite.org http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users
