Invalid Column Name when Create trigger using SQL server - sql

Question

I encountered several errors when I tried to create a simple trigger using SQL server. Tables are created using:
CREATE TABLE person
(
person_id INT NOT NULL PRIMARY KEY,
name VARCHAR NOT NULL,
phone INT,
birth_date DATE,
address VARCHAR
);
CREATE TABLE volunteers
(
person_id INT NOT NULL PRIMARY KEY,
skill VARCHAR,
FOREIGN KEY (person_id) REFERENCES person(person_id)
ON DELETE CASCADE
ON UPDATE CASCADE
);
CREATE TABLE physicians
(
person_id INT NOT NULL PRIMARY KEY,
speciality VARCHAR,
phone_number INT,
FOREIGN KEY (person_id) REFERENCES person(person_id)
ON DELETE CASCADE
ON UPDATE CASCADE
);
CREATE TABLE patients
(
person_id INT NOT NULL PRIMARY KEY,
contact_date DATE,
physician_id INT, -- TODO determine whether NULL able
-- TODO determine ON DELETE ACTION
CHECK (person_id <> physician_id),
FOREIGN KEY (person_id) REFERENCES person(person_id)
ON DELETE CASCADE
ON UPDATE CASCADE,
FOREIGN KEY (physician_id) REFERENCES physicians(person_id)
ON DELETE NO ACTION
ON UPDATE NO ACTION
);
CREATE TABLE outpatients
(
person_id INT NOT NULL PRIMARY KEY,
FOREIGN KEY (person_id) REFERENCES patients(person_id)
ON DELETE CASCADE
ON UPDATE CASCADE
);
CREATE TABLE visits
(
person_id INT NOT NULL,
date DATE NOT NULL,
comments VARCHAR,
PRIMARY KEY (person_id, date),
FOREIGN KEY (person_id) REFERENCES outpatients(person_id)
ON DELETE CASCADE
ON UPDATE CASCADE
);
CREATE TABLE employees
(
person_id INT NOT NULL PRIMARY KEY,
date_hire DATE,
FOREIGN KEY (person_id) REFERENCES person(person_id)
ON DELETE CASCADE
ON UPDATE CASCADE
);
CREATE TABLE nurses
(
person_id INT NOT NULL PRIMARY KEY,
certificate VARCHAR,
care_center_name VARCHAR,
FOREIGN KEY (person_id) REFERENCES employees(person_id)
ON DELETE CASCADE
ON UPDATE CASCADE,
-- FOREIGN KEY (care_center_name) REFERENCES care_centers(name)
-- ON DELETE CASCADE
-- ON UPDATE CASCADE
);
CREATE TABLE care_centers
(
name VARCHAR PRIMARY KEY NOT NULL,
nurses_in_charge INT NOT NULL,
location VARCHAR,
type VARCHAR
-- FOREIGN KEY (nurses_in_charge) REFERENCES registered_nurse(person_id)
);
CREATE TABLE registered_nurse
(
person_id INT NOT NULL PRIMARY KEY,
care_center_name VARCHAR,
FOREIGN KEY (person_id) REFERENCES nurses(person_id),
-- ON DELETE CASCADE
-- ON UPDATE CASCADE,
FOREIGN KEY (care_center_name) REFERENCES care_centers(name)
-- ON DELETE CASCADE
-- ON UPDATE CASCADE
);
ALTER TABLE nurses
ADD constraint nurses__care_centers_FK
FOREIGN KEY (care_center_name) REFERENCES care_centers(name)
ON DELETE CASCADE
ON UPDATE CASCADE;
ALTER TABLE care_centers
ADD constraint care_centers__registered_nurse_FK
FOREIGN KEY (nurses_in_charge) REFERENCES registered_nurse(person_id);
CREATE TABLE beds
(
bed_number INT NOT NULL,
room_number INT NOT NULL,
care_center_name VARCHAR,
PRIMARY KEY (bed_number,room_number),
FOREIGN KEY (care_center_name) REFERENCES care_centers(name)
ON DELETE CASCADE
ON UPDATE CASCADE
);
CREATE TABLE residents
(
person_id INT NOT NULL PRIMARY KEY,
date_admitted DATE,
bed_number INT,
room_number INT,
FOREIGN KEY (person_id) REFERENCES patients(person_id)
ON DELETE CASCADE
ON UPDATE CASCADE,
FOREIGN KEY (bed_number, room_number) REFERENCES beds(bed_number, room_number)
ON DELETE CASCADE
ON UPDATE CASCADE
);
CREATE TABLE staffs
(
person_id INT NOT NULL PRIMARY KEY,
job_class DATE,
FOREIGN KEY (person_id) REFERENCES employees(person_id)
ON DELETE CASCADE
ON UPDATE CASCADE
);
CREATE TABLE technicians
(
person_id INT NOT NULL PRIMARY KEY,
skill VARCHAR,
FOREIGN KEY (person_id) REFERENCES employees(person_id)
ON DELETE CASCADE
ON UPDATE CASCADE
);
CREATE TABLE laboratories
(
name VARCHAR NOT NULL PRIMARY KEY,
location VARCHAR
);
CREATE TABLE assignTechnicianToLab
(
person_id INT NOT NULL,
laboratories_name VARCHAR NOT NULL,
PRIMARY KEY(person_id, laboratories_name),
FOREIGN KEY (person_id) REFERENCES employees(person_id)
ON DELETE CASCADE
ON UPDATE CASCADE,
FOREIGN KEY (laboratories_name) REFERENCES laboratories(name)
ON DELETE CASCADE
ON UPDATE CASCADE
)
And the trigger I am trying to create:
-- Trigger
/* if nurse has certificate "RN", add to registered_nurse */
CREATE TRIGGER registered_nurse_trigger
ON nurses
FOR INSERT, UPDATE
AS
BEGIN
IF EXISTS (SELECT * FROM inserted where certificate = "RN")
BEGIN
INSERT INTO registered_nurse
VALUES(inserted.person_id, nurses.care_center_name);
END
END;
And I keep getting errors saying that:
Msg 207, Level 16, State 1, Procedure registered_nurse_trigger, Line 6
Invalid column name 'RN'.
Msg 4104, Level 16, State 1, Procedure registered_nurse_trigger, Line 8
The multi-part identifier "inserted.person_id" could not be bound.
Msg 4104, Level 16, State 1, Procedure registered_nurse_trigger, Line 8
The multi-part identifier "nurses.care_center_name" could not be bound.
I've been hanging over here for several hours and I really appreciate anyone can help me with it. Thank you very much!

Answer 1

You can't use VALUES() like that. Use INSERT..SELECT instead:
-- Trigger
/* if nurse has certificate "RN", add to registered_nurse */
CREATE TRIGGER registered_nurse_trigger ON nurses
For INSERT, UPDATE
AS BEGIN
INSERT INTO registered_nurse (person_id, care_center_name)
SELECT person_id, care_center_name
FROM inserted
WHERE certificate = 'RN'
END;
I don't think you need to reference nurses or have that EXISTS() either, but maybe I'm overlooking something.

Answer 2

You are using double quote instead of single quotes in your Create Trigger statement try this and see if it works:
-- Trigger
/* if nurse has certificate "RN", add to registered_nurse */
CREATE TRIGGER registered_nurse_trigger ON nurses
FOR INSERT, UPDATE
AS
BEGIN
IF EXISTS (SELECT * FROM inserted where certificate = 'RN')
BEGIN
INSERT INTO registered_nurse
SELECT person_id, care_center_name FROM Inserted;
END
END;