SQL ERROR: This is not permitted when the subquery follows =, !=, <, <= , >, >= or when the subquery is used as an expression

Question

I got this error in SQL Server 2012:

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

This is my script:

CREATE PROCEDURE dbo.Update_F_ARTCLIENT

@PK varchar(19)
,@AR_Ref varchar(19)
,@AC_Categorie smallint
,@AC_PrixVen numeric(24,6)
,@AC_Coef numeric(24,6)
,@AC_PrixTTC smallint
,@AC_Remise numeric(24,6)

AS
BEGIN

SET NOCOUNT ON;

UPDATE [dbo].[F_ARTCLIENT]

SET

[AR_Ref] = @AR_Ref
,[AC_Categorie] = @AC_Categorie 
,[AC_PrixVen] = @AC_PrixVen
,[AC_Coef]= @AC_Coef
,[AC_PrixTTC] = @AC_PrixTTC
,[AC_Remise] = @AC_Remise

WHERE (SELECT CONCAT([AR_Ref], [AC_Categorie]) as PK FROM [dbo].[F_ARTCLIENT])= @PK

END

Answer 1

As the error description reports, your subquery return more than a value. You can avoid this changing your subquery in this way:

(SELECT TOP 1 CONCAT([AR_Ref], [AC_Categorie]) as PK FROM [dbo].[F_ARTCLIENT])= @PK)

Answer 2

尝试将WHERE条件修改为：

WHERE CONCAT([AR_Ref], [AC_Categorie]) = @PK

Answer 3

The problem is clearly in the where clause. Presumably, you want to do the update where this condition is true. One pay is to change the logic to an in :

WHERE @pk in (SELECT CONCAT([AR_Ref], [AC_Categorie]) as PK FROM [dbo].[F_ARTCLIENT])

However, I notice that the table in the subquery is the same as the data being updated. Do you really just mean this:

WHERE @pk = CONCAT([AR_Ref], [AC_Categorie])

That is, I don't think the subquery is necessary.