Function names must be unique

Author: simon-dew

modules/n1ql/pages/n1ql-language-reference/createfunction.adoc

@@ -153,7 +153,7 @@ include::partial$grammar/ddl.ebnf[tag=function]
 image::n1ql-language-reference/function.png["Syntax diagram: see source code listing", align=left]
 
 The function name specifies the name of the function to create.
-It is recommended to use an unqualified identifier for the function name, such as `func1` or `{backtick}func-1{backtick}`.
+It's recommended to use an unqualified identifier for the function name, such as `func1` or `{backtick}func-1{backtick}`.
 In this case, the function is created as a global function or a scoped function, depending on the current query context.
 
 To create a global function in a particular namespace, the function name must be a qualified identifier with a namespace, such as `default:func1`.
@@ -162,6 +162,10 @@ Similarly, to create a scoped function in a particular scope, the function name
 If the function name is an unqualified identifier, it may not be the same as a reserved keyword.
 A function name with a specified namespace or scope may have the same name as a reserved keyword.
 
+The function name must be unique within its scope or namespace.
+You cannot have two functions with the same name inside the same scope or namespace.
+You can have two functions with the same name across different scopes or namespaces.
+
 [id='{section}-parameter']
 ==== Function Parameters