Trigger | how to get child records when add the record in parent table

[Shintaro]

Hello,

I have 3 tables.

1. Exchange cash table (parent table)
2. cash in register table (child table)
3. cash out register table (child table)

What I want to do is  when a user exchange a cash, send me email.
So I created 2 virtual columns in exchange cash table.
1. for cash out data like "[cash:1000 num:1, cash:500 num:1] ",
2. for cash in data like "[cash:100 num:100, cash:50 num:10] "

Trigger is:
add new record in Exchange cash table.

Here is the question.

When the trigger get fired, there are null record in 2 virtual columns because I think cash in & cash out table have not created new records yet.

So I don't know how to solve this problem..

[Marc_Dillon]

Don't trigger the bot on parent record addition, trigger it later.