Q3: explain the important term “trigger-event”, in relation to “trigger-action”
Q: can a trigger-event invoke both a before-action and an after-action?
A: yes
Q: can a trigger-action be defined with select-statements alone? Does it make sense?
Q: can a trigger-action call stored programs?
A: yes
Q8: Beside before-action and after-action, what other trigger-actions are supported?
A8: for-each-row-action is NOT a third type. Both mysql and oracle let you combine BEFORE and for-each-row
Q: what if a DML where-clause matches no record? Will a before-action run? How about an after-action?
A3: an insert on a table, a delete on a table, or an update OF one or more columns ON a table. In some databases(which?), a call to a stored procedure also qualifies as a trigger event