An index has to be built from actual data. You would need to evaluate the expression and make the result a column in a table.
c.panel wrote: > Oh yes! "set" is the solution. > I know that I have missed something... > thanks a lot. > > no possibilities for indexing on an expression : is it a particularity of > SQL or SQLite ? > > > Igor Tandetnik wrote: > >>c.panel <[EMAIL PROTECTED]> wrote: >> >>>I'm learning SQL and SQLite C API. >>> >>>1)Suppose I have a table with many columns indexed on a column. >>>I want to change one value in a column only. >>>How can I make it with SQL ? >> >>If I understand your question, you want something like this: >> >>update tableName set columnName=:newValue where columnName=:oldValue; >> >> >>>2)Is it possible to index a table on an expression (composed from >>>column names) ? >> >>No. >> >>Igor Tandetnik >> >> >> >>_______________________________________________ >>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
