Here you can find the source of NVL(String value, String replace)
public static String NVL(String value, String replace)
//package com.java2s; public class Main { public static String NVL(String value) { return (value == null ? "" : value.trim()); }/* w ww . j ava 2 s . c om*/ public static String NVL(String value, String replace) { return (value == null || value.equals("") ? replace : value.trim()); } }