Tinit and Tmain are two separate transactions. I usually use Tinit to "initialzie" the application or get the application to a state that allows me to repeat the Tmain transaction. For example, I may want the users to login once and then repeat a specific business transaction multiple times. If I have the script setup like this:
Tinit : begin;
Tmain : 1;
The code in Tinit will be executed once and the code within Tmain will be executed multiple times.
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