On 16 May 2011, at 7:18pm, Jay A. Kreibich wrote: > I think the bigger issue is that column rename requires full > understanding of the SQL statements stored in sqlite_master. To > safely do a ALTER TABLE...RENAME COLUMN you have to understand the > context and parts of the CREATE TABLE statement (and triggers, and > indexes, and FKs of other tables). This requires a close link between > the modification function, the parser, and the tokenizer. You have to > scan the SQL statement and understand the different parts, and then > back-trace them to a specific character in the original statement, > so you know which substring to change. While this is feasible, most > tokenizers and parsers are specifically designed to be abstract layers.
Yet strangely, the ability to obtain the statements used to create the schema is something I find very useful in quite a few utilities. If you could depend on them being in a standard format they'd be even more useful. MySQL has a way to obtain the data in statement form too. Imagine a command like SELECT AS INSERT COMMANDS * FROM myTable WHERE joinDate > '2001' which returns one field of text per record, with each piece of text being the INSERT command required to reproduce it: INSERT INTO myTable (id,name,address,joinDate) VALUES (123,'Fred Savage','12 Rowantree Crescent','20020115') It gives a great way to tokenise a record. Simon. _______________________________________________ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
