>From a mathematical standpoint in your example, going back to grade 4 math (35 years ago for me. *sigh*. I'm so sad....), where clause works based off of standard order of operations based on BEDMAS and eventually working things down to booleans. In your example, the math would be processed as 3+5*4+3 3+20+3 23+3 26
BEDMAS doesn't cover boolean logic, however, so FYI 'AND' is grouped as one thing and 'OR' is grouped as another. So: WHERE A = 1 AND B = 2 OR C = 3 evaluates differently to WHERE A = 1 OR B = 2 AND C = 3 In the first case, A and B have to meet the conditions, or C has to meet the conditions. In the second case, A has to meet the condition or B and C has to meet the conditions. I've never tried or needed XOR or NAND or any other type of evaluator so I don't know if SQLite is aware of the other types of boolean algebra. Von: Prakash Premkumar [mailto:prakash.p...@gmail.com] > Gesendet: Montag, 10. November 2014 10:40 > An: General Discussion of SQLite Database > Betreff: [sqlite] SQLite where clause tree > > The where clause in sqlite is encoded as a tree > > Let's say I have select statement like : > > SELECT * from employee where salary = 3+5*4+3; > > The tree which takes care of operator precedence is : > > = > / \ > salary + > / \ > 3 3 > / > * > / \ > 5 4 > > If I am constructing this tree for where clause by myself, should i take > the operator precedence in to account while constructing it or will sqlite > take care of precedence,given any tree (i.e constructing it with out taking > precedence into account) ? > > Kindly give me some pointers towards this tree construction Thanks a lot > for your time. > > Regards > Prakash > _______________________________________________ > sqlite-users mailing list > sqlite-users@sqlite.org > http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users > > > ___________________________________________ > Gunter Hick > Software Engineer > Scientific Games International GmbH > FN 157284 a, HG Wien > Klitschgasse 2-4, A-1130 Vienna, Austria > Tel: +43 1 80100 0 > E-Mail: h...@scigames.at > > This communication (including any attachments) is intended for the use of > the intended recipient(s) only and may contain information that is > confidential, privileged or legally protected. Any unauthorized use or > dissemination of this communication is strictly prohibited. If you have > received this communication in error, please immediately notify the sender > by return e-mail message and delete all copies of the original > communication. Thank you for your cooperation. > > > _______________________________________________ > 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
