On 2016/11/23 2:08 AM, Scott Hess wrote:
https://www.sqlite.org/pragma.html has: "No error messages are generated if an unknown pragma is issued. Unknown pragmas are simply ignored. This means if there is a typo in a pragma statement the library does not inform the user of the fact." I just lost some time due to this, even though I was fully aware of it. My code wasn't working, so I instrumented to report errors, and gradually dug things deeper and deeper. It wasn't until I was verifying statements line-by-line against sqlite3 in a terminal window that I saw that I was setting journal_mod rather than journal_mode! I realize that pragma don't have the compatibility guarantees that other syntax has. But that means I actually _would_ want my code to start barfing if a PRAGMA stops being supported. Say I'm issuing "PRAGMA secure_delete=ON" - presumably it's for a reason, and I'm going to want to revisit that reason if it's no longer supported.
The problem is more the other way round - Backward compatibility is hard when you introduce a new pragma, and a previous version of SQLite "barfs" suddenly when it encounters that statement. Recent posts here re-emphasize the frequency with which old versions are still used out there....
Silently ignoring an unrecognized pragma is a great way to be able to introduce new functionality without worrying that the old will break.
That said - we have been lobbying a long time for a "Strict-Mode" in SQLite (though that would probably hurt the "lite-ness" of it), but this is another example where such a mode would prove very useful.
Also - there are many tools that will syntax-check and/or use code-highlighting for your SQL for SQLite (SQLitespeed found here: www.sqlc.rifin.co.za or sqliteexpert.com being two of them and others regularly pop up here) which would high-light such problems. If you do not wish to check ALL your statements, at least try those that break on one of these systems before starting a big dig.
Good luck! Ryan _______________________________________________ sqlite-users mailing list sqlite-users@mailinglists.sqlite.org http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users
