SQL Server 2017

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CREATE TABLE BooksA(
  BookID INT,
  BookPrice MONEY
);

CREATE TABLE BooksB(
  BookID INT,
  BookPrice MONEY
);

CREATE TABLE BooksC(
  BookID INT,
  BookPrice MONEY
);

INSERT INTO BooksA VALUES
(1, 100),
(2, 200),
(3, 100);

INSERT INTO BooksB SELECT * FROM BooksA;
INSERT INTO BooksC SELECT * FROM BooksB;
9 rows affected

CREATE TRIGGER Trig1
ON BooksA
AFTER UPDATE
AS
BEGIN
IF UPDATE(BookPrice)
  BEGIN
    UPDATE BooksB
    SET BookPrice = I.BookPrice
    FROM BooksB INNER JOIN INSERTED I
    ON BooksB.BookID = I.BookID;
    --
    UPDATE BooksC
    SET BookPrice = I.BookPrice
    FROM BooksC INNER JOIN INSERTED I
    ON BooksC.BookID = I.BookID;
  END
END
UPDATE BooksA
SET BookPrice = 500
WHERE BookPrice = 100;

SELECT * FROM BooksA;
SELECT * FROM BooksB;
SELECT * FROM BooksC;


BookID
BookPrice


1
500.0000

2
200.0000

3
500.0000




BookID
BookPrice


1
500.0000

2
200.0000

3
500.0000




BookID
BookPrice


1
500.0000

2
200.0000

3
500.0000