On Fri, 16 Sep 2016 16:59:17 +0200 Dominique Devienne <ddevie...@gmail.com> wrote:
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> Is that <<WHERE col IN tab>> SQL standard? No. The two most frequently used pointless words in SQL are "select *". The SELECT clause (not statement) chooses columns; in relational algebra terms, it's a project operator. If "all columns" is what you need, what you don't need is projection. Requiring "select *" makes as much sense as requiring "WHERE TRUE" if there is no restriction. The strict select-from-where construct in SQL is an artifact of its roots in IBM's 1970s-era "4th generation" languages. That's why the language looks so much like Cobol and so little like math. But it is what it is. In SQL, a tablename is a parameter for FROM (and nowadays, JOIN). Predicates -- IN, EXISTS -- take SELECT. --jkl _______________________________________________ sqlite-users mailing list sqlite-users@mailinglists.sqlite.org http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users
