sql - 如果该列中不存在列值,则插入列值

Question

sql - 如果该列中不存在列值,则插入列值

Answer 1

嗯.你想要一个新行吗？在这种情况下,

 IF NOT EXISTS(SELECT 1 FROM emp WHERE fruits = 'mango')
    INSERT INTO emp (fruits) VALUES ('mango')

Answer 2

两种方法

1.IF NOT EXISTS (SELECT fruit FROM emp WHERE fruit='mango') 
BEGIN 
INSERT INTO emp(fruit) Values('mango'); 
END 

2.INSERT INTO emp ('mango') SELECT distinct fruit FROM emp WHERE not exists (select fruit from emp as e Where emp.fruit = e.fruit);