mysql - Transaction necessary for single update query? -


i have mysql query on innodb table this:

update items set qty = qty + 5 item_id = 1234 limit 1;

do need use transaction this? undesirable happen not using transaction?

nothing serious can happen. default, mysql wraps single update/insert/delete commands in transaction. if goes wrong in update, transaction should rolled correctly.

you need transactions when combining multiple changes , want them take effect "at same time" or "not @ all".

you can read more in documentation.


Comments

Post a Comment

Popular posts from this blog

How to logout from a login page in asp.net -

whenever click on logout button redirect me login page when im clicking on button redirect me last visited page. not using membership or windows authentication. session.abandon(); response.cache.setcacheability(httpcacheability.private); response.cache.setcacheability(httpcacheability.nocache); response.redirect("loginform.aspx"); if using session destroy session value on logout button click , can put check in app webpages if(session["sessionvaribale"].equals(null)) { response.redirect("logoutpage url"); }
Read more

PHP Error "Undefined index" -

hello i'm trying login system working on site , error saying notice: undefined index: user_login in c:\wamp\www\justbetweenfriends\home.php on line 4 . the database works , everthing else works besides error i'm getting now. home.php code <?php error_reporting(e_all ^ e_deprecated); ?> <?php include ( "./inc/header.inc.php" ); echo $_session["user_login"]; ?> full code index.php <?php error_reporting(e_all ^ e_deprecated); ?> <?php include( "./inc/header.inc.php" ); ?> <?php $reg = @$_post['reg']; //declaring variables prevent errors $fn = ""; //first name $ln = ""; //last name $un = ""; //username $em = ""; //email $em2 = ""; //email 2 $pswd = ""; //passoword $pswd2 = ""; // password 2 $d = ""; // sign data $u_check = ""; // check if username extsts //registration form $fn = strip_tags(@$_post...
Read more