CODEWITHSUNDEEP
mysqlsql
weggie
weggie

Reputation: 447

Adding data to column to activate a trigger then removing it

I have a mysql table that has a trigger that will activate when an update is performed. I would like to force this trigger to run by adding a value to the last name but only for specific users.

What I'm thinking is to make this work, I would need to take the value of the lname and add something to it like '$'. This would make the trigger run and then rerun some SQL to remove the '$' from the lname.

I think it would look something like this:

Update table set lname = (current_value_OF_LNAME & "$")
where active = 1

Then

Update table set lname = (Remove($ from current_value_OF_LNAME)

Sorry for the pseudo code but I wanted to put this out there to see if this is the best way to do this or if there is a better way. Or if there is a way to just force this to run that would be acceptable too.

Thanks and sorry for the questions being muddy.

Upvotes: 0

Views: 41

Answers (1)

hol
hol

Reputation: 8423

Something like this

Update table set lname = concat(lname,'$') 
 where active = 1

then

Update table set lname = substr(lname,1,length(lname)-1)
 where active = 1

Are you alone on the DB or could more rows be added or updated. I hope not. If yes you may query like this (still not perfect but helps)

Update table set lname = substr(lname,1,length(lname)-1)
 where substr(test,-1) = '$'

Upvotes: 1

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