Subquery returned more than 1 value. This is not permitted when the subquery follows =, !=, <, <= , >, >= or when the subquery is used as an expression. 'Document' (RDOC)

Question

how to identify the field that brings more than one value? when I run the store procedure I don't see the error

Answer 1

Hi @Yefer Bastidas
Sorry for not checking your code carefully yesterday.And as experts said ,there are indeed some subqueries in your code that may return more than 1 value.
As you can see from the error message,there are two situations that can cause this error.

First : when the subquery follows =, !=, <, <= , >, >=

and I believe you have double checked this situtuation.

Second : when the subquery is used as an expression

Please refer to this sample:

CREATE TABLE #TEST1(ID INT,Column_1 VARCHAR(10));  
INSERT INTO #TEST1 VALUES(1,'AA') ,(2,'BB');   
CREATE TABLE #TEST2(ID INT,Column_2 INT);  
INSERT INTO #TEST2 VALUES(1,100) ,(2,200) ,(3,300);   

--Subquery returned only 1 value.  
SELECT *,(SELECT Column_2 FROM #TEST2 WHERE Column_2 = 100) AS 'Number'  
FROM #TEST1;  
--Subquery returned more than 1 value.  
SELECT *,(SELECT Column_2 FROM #TEST2 WHERE Column_2 > 100) AS 'Number'  
FROM #TEST1;  

So you need to check statements such as: SELECT ...,subquery AS alias , ISNULL(subquery, '') in your code,.

Best Regards,
LiHong

Answer 2

Thank you all, I am taking all your recommendations and will review each of the subqueries