The NVL function of Orcale and the IsNull function of SQL Server

The NVL function of orcal

NVL (EXPR1,EXPR2) If EXPR1 is null, returns the value of EXPR2, otherwise returns the value of EXPR1, EXPR1,EXPR2 null returns null  
 
 nvl2 (EXPR1,EXPR2,EXPR3) If EXPR1 is null, Returns the value of EXPR2, otherwise returns the value of EXPR3  
 
 nullif (EXPR1,EXPR2) If the values of EXPR1 and EXPR2 are equal, returns NULL, Otherwise returns the value of Expr1 
  
 coalesce (Expr1, EXPR2, Expr3 ..... EXPRN)  represents a placeholder for multiple expressions that can be specified. All expressions must be of the same type, or can be implicitly converted to the same type. Returns the first null value  
   
 return value type   
  
    sql server    
  ISNULL (check_expression, replacement_value)  

Parameters
Check_expression is an expression that will be checked for null. Check_expression can be of any type.

Replacement_value The expression that will be returned when check_expression is null. Replacement_value must have the same type as Check_expresssion

The NVL function of Orcale and the IsNull function of SQL Server