CREATING A TRIGGER THAT PICKS UP THE LAST INSERTED RECORD

Question

Hello everybody
my question. is it possible to embed a sql query whitin a trigger? the thing is that when I have to insert the value, this actually would have to be retrieved from another table. It is an AFTER INSERT, but it needs to know which name I inserted in table 1 in order to also insert it into table 2.
More specifically. Imagine a table with usernames and passwords that I populate as I set them up
Then I need a trigger that as it sees that I have entered that username it takes it and populates another table with that plus a generated sequence that could be the result of some string function
CREATE OR REPLACE
TRIGGER GENERATE_SEQUENCE
AFTER INSERT ON USERS_TABLE
FOR EACH ROW
BEGIN
insert into GENERATED_SEQUENCES_TABLE (lastinserted_name,surrogate_key)
values(SELECT USERNAME FROM USERS_TABLE WHERE USERID....., SUBSTR (lastinsertedname¦¦ password), 1,12);
END;
so, this lastinserted name is what I am trying to retrieve. I mean if it is not madness to insert a sql query in the way I have done it, I could write in the query to select the highest ID from the PK and that would give me the last inserted name.
thanks a lot
Alvaro

Answer 1

In an insert trigger you can reference all the inserting values with :new.column_name, hence there's no need to select from the USERS_TABLE table:
CREATE OR REPLACE
TRIGGER GENERATE_SEQUENCE
AFTER INSERT ON USERS_TABLE
FOR EACH ROW
BEGIN
insert into GENERATED_SEQUENCES_TABLE (lastinserted_name,surrogate_key)
values(:new.USERNAME, ...);
END;
/Max
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