文章目录

• 1 概述
• 2 示例
• • 2.1 验证1：通过调试面板
  • 2.2 验证2：通过工作表
• 3 官方文档解释

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let var_is_null = IsNull(Null());  // -1
let var_is_not_null = IsNull('a'); // 0

测试表:
select 'a' 非空列,null 空列from dual;