Documented here: https://sqlite.org/opcode.html
Concat Add the text in register P1 onto the end of the text in register P2 and store the result in register P3. If either the P1 or P2 text are NULL then store NULL in P3. P3 = P2 || P1 It is illegal for P1 and P3 to be the same register. Sometimes, if P3 is the same register as P2, the implementation is able to avoid a memcpy(). -----Ursprüngliche Nachricht----- Von: sqlite-users [mailto:[email protected]] Im Auftrag von Dominique Devienne Gesendet: Freitag, 04. Jänner 2019 10:48 An: General Discussion of SQLite Database <[email protected]> Betreff: [EXTERNAL] [sqlite] Concatenating text literals with NULL yields NULL I was just surprised by this behavior, see below. Googling it, seems like SQL Server has a setting the change the behavior in that case. Is this standard SQL behavior, as implemented in SQLite? Not complaining, just asking whether I can depend on it, or not. Thanks, --DD C:\Users\ddevienne>sqlite3 SQLite version 3.25.3 2018-11-05 20:37:38 Enter ".help" for usage hints. Connected to a transient in-memory database. Use ".open FILENAME" to reopen on a persistent database. sqlite> create table t(v); sqlite> insert into t values (null); sqlite> select v from t; sqlite> select '('||v||')' from t; sqlite> select typeof('('||v||')') from t; null _______________________________________________ sqlite-users mailing list [email protected]<mailto:[email protected]> http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users ___________________________________________ Gunter Hick | Software Engineer | Scientific Games International GmbH<http://www.scigames.at> | Klitschgasse 2-4, A-1130 Vienna | FN 157284 a, HG Wien, DVR: 0430013 | (O) +43 1 80100 - 0 May be privileged. May be confidential. Please delete if not the addressee. _______________________________________________ sqlite-users mailing list [email protected] http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users
