What analysis are you performing which causes you to conclude that nothing is being delayed? I'd probably check this by creating an insert...select which takes at least a few seconds to execute, and then have my test application log the time, make the call to MySQL, and log the time again. I suppose you could probably do something with locking instead of making the insert slow, but I'm never very confident that the database won't secretly execute my statement and delay exposing the altered table to the locking thread until it unlocks. (I'm pretty sure MySQL won't do this, but I'm superstitious.)
The online docs for DELAYED do seem a bit confusing. I don't think of DELAYED in terms of its interaction with other threads-- I think MySQL actually still provides the guarantee that SQL statements will be executed in order, although some of the docs here appear to contradict that. My view on DELAYED is that it does nothing more than make the call to the database asynchronous. Instead of calling MySQL, waiting for your statement to execute, and returning, executing a DELAYED statement results in calling MySQL, returning, and letting the statement execute asynchronously with your own thread. Although the async call happens on the server side of the connection, you can get a pretty much equivalent effect by simply spawning a new thread (with its own independent connection to MySQL) and letting it send your statement for you. Clearly, this wouldn't necessarily affect the order of execution of SQL statements in the server at all; it just lets you get on with your other work while the server is working. -Rob PS: No pedantic comments about locking, synchronization, and connection ordering with respect to thread-spawning, please; it was just an example. On 29/4/02 at 2:11 pm, Emery Lapinski <[EMAIL PROTECTED]> wrote: > Hello, > > I'm trying to use the DELAYED keyword with an INSERT ... SELECT > statement but it seems to ignore the DELAYED. Does anyone know if this > is or is not supposed to work? Exmple: > > session 1 session 2 > ------------------------------- -------------------------------------- > create table junk (value int); > create table junk2 (value int); > lock table junk read; > insert into junk2 values (1); > insert delayed into junk values (2); > insert delayed into junk select value > from junk2; > unlock tables; > > http://www.mysql.com/doc/I/N/INSERT_SELECT.html > http://www.mysql.com/doc/I/N/INSERT_DELAYED.html > > Thanks, > Emery --------------------------------------------------------------------- Before posting, please check: http://www.mysql.com/manual.php (the manual) http://lists.mysql.com/ (the list archive) To request this thread, e-mail <[EMAIL PROTECTED]> To unsubscribe, e-mail <[EMAIL PROTECTED]> Trouble unsubscribing? Try: http://lists.mysql.com/php/unsubscribe.php
