The script doesn't treat my parameters as variables

[royzhang]

Hi,
I'm pretty new in tcl. I made the following proc log_event. There are three parameters passed: "msgid, state and status".
When I called "log_event dkflj fjlksd fdjls",
the script doesn't treat the parameter as variables! I appreciate if anyone can shed a light on it.

mysql> select * from logging;
+----+--------+--------+---------+------------+
| id | MID | STATE | STATUS | DATE |
+----+--------+--------+---------+------------+
| 51 | $msgid | $state | $status | 2011-08-29 |
+----+--------+--------+---------+------------+


----------------------------------------------------------
#!/cygdrive/c/Tcl/bin/tclsh

proc log_event {msgid state status} {

package require mysqltcl
global mysqlstatus

set port {3306}
set host {localhost}
set user {root}
set password {gofish}
set db {event_logging}

set handler [mysqlconnect -host $host -port $port -user $user -password $password -db $db]

mysqlexec $handler {insert into logging(mid,state,status,date) values('$msgid','$state','$status',now())}

set query [mysqlsel $handler {select * from logging} -flatlist]
puts $query
mysqlclose $handler

}

log_event dkflj fjlksd fdjls
----------------------------------------------------------------


$ ./2.tcl
51 {$msgid} {$state} {$status} 2011-08-29

 

[Bong]

Try using "" instead of {} in the mysqlexec call.

_________________
Bob Rashkin

 

[royzhang]

Thanks million Bob, It's working!!! Can you give me a hint why the reason?

 

[Bong]

In Tcl there are varying levels of delayed substitution. That is, when you say, for instance, "$varname", at what point in the evaluation of the script will the current value of the variable named, "varname", be substituted for the placeholder, "$varname".

"" means immediately. {} means when the step is executed. In your case, I think the single quotes (' ') inside the brackets ({}) were essentially making the substitution permanently delayed. For an experiment, try returning to the brackets and take out the single quotes altogether.

_________________
Bob Rashkin

 

[royzhang]

Good explanation!
I did put back the brackets and take out the single quotes, got unknown column error. Single quote may be necessary by sql.