Am 02.12.2014 18:31, schrieb Johan De Meersman: > ----- Original Message ----- >> From: "wharms" <wha...@bfs.de> >> Subject: signal handling in mysql cli >> >> when i use CTRL-C to break a query that works fine in interactive mode. >> >> but when i use the noninteractive mode >> i looks like that but "show full processlist;" shows otherwise and that is >> true > > This may sound silly, but you're basically saying that you can't interact > with it while in non-interactive mode... > > My understanding may be wrong, but this is how it works in my mind: > * when in the client, the client intercepts the ctrl-c and interprets it as > "kill this query on the server". > * when in non-interactive mode, the client is not actually reading your > keypresses. Thus, the ctrl-c gets intercepted by the *shell*, which does > exactly what you ask by killing the MySQL client process. > > Now, if the mysql client does not explicitly intercept kill signals - which, > honestly, most programs have no reason to - that means it doesn't even get a > chance to send the "cancel that query" order, it just dies. > > A lot of debate could be put in on wether or not the client needs to > intercept and send a cancel, but personally I'm leaning towards "no, it > doesn't" - if you don't have a transaction open, or don't even have a > transactional engine (which used to be default!) cancelling would leave your > database in an inconsistent state. Much better, then, to allow whatever query > you sent to continue, on the off chance that it's something that it does not > damage, or only does things that you can reverse afterwards. If you really > want to kill that query, you always have the option of logging into the > server and shooting it yourself. >
In Unix pressing CTRL-C should be the same a sending a INTR. You can see this with stty -a what key is map to what signal. NTL the question is: how can the user stop the query what was started with a script ? re, wh -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe: http://lists.mysql.com/mysql
