摘要:
解构数组 var [a,b]=[1,2]; a //1 b //2 var [a,b]=[1,2,3,4]; a //1 b //2 var [a,,b]=[1,2,3,4]; a //1 b //3 var a,b; [a=3,b=2]=[1]; //默认值 a //1 b //2 var [a, 阅读全文
摘要:
mysql 1 每个语句的结束记得加分号; 2where条件里再做if分支 SELECT *FROM `table` WHERE IF( `parentID` is null, `plan_id` <10, `plan_id` >500 ) 还可以再嵌套使用 WHERE IF(device_id i 阅读全文