On 31 Jan 2015, at 11:14pm, James K. Lowden <jklow...@schemamania.org> wrote:
> That said, https://www.sqlite.org/datatype3.html says REAL is "stored > as an 8-byte IEEE floating point number". I can't see why a > non-signalling NaN couldn't be stored and interpreted. You'd need some > convention for collation, and a function like is_nan() would be helpful > for WHERE clauses. So, having established that NaN and -0 do not make the round trip from a C variable through a database and back into a C variable ... at least I think we have ... There's a bit representation for storing NaN in a binary64. Presumably, if you have NaN in a C variable, it's using that representation in memory. Then you use sqlite3_bind_double() to get this into an SQLite variable, and use INSERT to get SQLite to put that into a database. Do we expect to be able to see that pattern by looking through the database file using hexdump ? Because there's nothing in the SQLite documentation that says it can store values like NaN or -0.0. The documentation just says it can store numbers. It should be possible to find out when the distinction between 0.0 and -0.0 gets lost. Simon. _______________________________________________ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
