In this blog post, let’s learn about the error message “134 – The variable name ‘%.*ls’ has already been declared. Variable names must be unique within a query batch or stored procedure.” in Microsoft SQL Server, the reason why it appears and the solution to fix it.
SQL Server Error Message
134 – The variable name ‘%.*ls’ has already been declared. Variable names must be unique within a query batch or stored procedure.
Reason for the Error
SQL Server Error Msg 134 occurs when a variable is declared with a name that has already been used in the same query batch or stored procedure. This error message indicates that SQL Server requires each variable name to be unique within its scope.
Here is an example of how this error can occur:
DECLARE @counter INT = 0; DECLARE @counter INT = 1;
In this example, the code block attempts to declare two variables with the same name, @counter. This will result in SQL Server throwing an error message similar to the following:
Msg 134, Level 15, State 1, Line 2
The variable name ‘@counter’ has already been declared. Variable names must be unique within a query batch or stored procedure.
Solution
To resolve this error, ensure that each variable name is unique within its scope. You can either rename one of the conflicting variables or remove one of the declarations entirely. For example:
DECLARE @counter1 INT = 0; DECLARE @counter2 INT = 1;
In this updated example, the variables have been renamed to be unique and the error should no longer occur.
