Answer Posted / koteswara reddy

If row level trigger based on a table than trigger body cannot read data from same table and also we can't perform dml operations on a same table. if anybody trying this then oracle server returns an error. this error is called mutating error and table is called mutating table
ex:-
create or replace trigger trg
after delete on emp
for each row
declare
l_count number;
begin
select count(*) into l_count from emp;
dbms_output.put_line(l_count);
end;
/

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