- NEW
NEW is a pseudo-record name that
refers to the new table row for insert and update
operations in row-level triggers. This variable is
not applicable in statement-level triggers and in
delete operations of row-level triggers.
Its usage is:
:NEW.column
where column is the name of
a column in the table on which the trigger is defined.
The initial content of
:NEW.column
is the value in the named column of the new row to be
inserted or of the new row that is to replace the old one
when used in a before row-level trigger. When used in
an after row-level trigger, this value has already been
stored in the table since the action has already occurred
on the affected row.
In the trigger code block,
:NEW.column
can be used like any other variable. If a value is
assigned to
:NEW.column,
in the code block of a before row-level trigger, the
assigned value will be used in the new inserted or updated row.
- OLD
OLD is a pseudo-record name that
refers to the old table row for update and delete
operations in row-level triggers. This variable is
not applicable in statement-level triggers and in
insert operations of row-level triggers.
Its usage is:
:OLD.column
where column is the name of
a column in the table on which the trigger is defined.
The initial content of
:OLD.column
is the value in the named column of the row to be
deleted or of the old row that is to replaced by the new one
when used in a before row-level trigger. When used in
an after row-level trigger, this value is no longer stored
in the table since the action has already occurred
on the affected row.
In the trigger code block,
:OLD.column
can be used like any other variable. Assigning a value to
:OLD.column,
has no affect on the action of the trigger.
- INSERTING
INSERTING is a conditional expression
that returns true if an insert operation fired the trigger,
otherwise it returns false.
- UPDATING
UPDATING is a conditional expression
that returns true if an update operation fired the trigger,
otherwise it returns false.
- DELETING
DELETING is a conditional expression
that returns true if a delete operation fired the trigger,
otherwise it returns false.
