create row number in sql

SELECT t.A, t.B, t.C, ROW_NUMBER() OVER (ORDER BY t.A) as newId
  FROM dbo.tableZ AS t
  ORDER BY t.A;

-- Uses AdventureWorks  
  
SELECT ROW_NUMBER() OVER(ORDER BY SUM(SalesAmountQuota) DESC) 
    AS RowNumber,  
    FirstName, LastName,   
    CONVERT(varchar(13), SUM(SalesAmountQuota),1) AS SalesQuota   
FROM dbo.DimEmployee AS e  
INNER JOIN dbo.FactSalesQuota AS sq  
    ON e.EmployeeKey = sq.EmployeeKey  
WHERE e.SalesPersonFlag = 1  
GROUP BY LastName, FirstName;  

SELECT 
   ROW_NUMBER() OVER (
 ORDER BY first_name
   ) row_num,
   first_name, 
   last_name, 
   city
FROM 
   sales.customers;