select schedulerid from circuit where schedulerid not in (null);
查询结果:
|SCHEDULERID|
+----------------------+
结论:任何与null的比较(<,>,=,>=,<=,between and )和 in,not in等等的结果都是false。
心得:养成对select,insert,where子句使用nvl的习惯。警惕子查询的结果中是否有null值。
select schedulerid from circuit where schedulerid not in (null);