可以用ploop 函数并行计算: unionAll(ploop(fromJson, s1), false)
回答于 2021-06-15 14:48
可以用下面代码: select nullFill(t1.time, t2.time) as time, value, qty from fj(t1, t2, `time) order by nullFill!(t1.time, t2.time) 或者 (select nullFill(t1.time, t2.time) as time, value, qty from fj(t1, t2, `time)).sortBy!(`time)
回答于 2021-06-15 14:47
可试试下面代码: def dataTransform(mutablet){ return t.replaceColumn!(`SendingTimeInNano, nanotimestamp(t.SendingTimeInNano)).replaceColumn!(`origSendingTimeInNano, nanotimestamp(t.origSendingTimeInNano)) } pt=loadTextEx(dbHandle=db,tableName=`nx , partitionColumns=`SendingTimeInNano`securityI...
回答于 2021-06-15 14:46
这个可通过shell脚本实现。也可通过在DolphinDB中调用shell函数实现。下面的例子代码创建了一个定时作业,实现了每天凌晨删除1天前的定时作业运行日志和返回值。 def rmBatchJobLog(){ path=getHomeDir()+"/batchJobs" filenames=exec filename from files(path) where filename like "%.obj" or filename like...
回答于 2021-06-15 14:43
fromJson不能接受向量作为参数,可以用each函数来实现: x1='{"name":"","form":"scalar","type":"double","value":"2.1E+5"}' x2='{"name":"","form":"scalar","type":"double","value":"100"}' t=table(1..2 as id,[x1,x2] as val) select id,each(fromJson,val) from t
回答于 2021-06-15 14:39
DolphinDB database最新版提供了cgroup by(cumulative group)功能。cgroup by子句可进行累计分组计算,第二组的记录包含第一个组的记录,第三个组的记录包含前两组的记录,以此类推。详情请参阅https://www.dolphindb.cn/cn/help/SQLStatements/cgroupby.html
回答于 2021-06-15 14:36
imes的类型不对,可用typestr看一下,改成如下: times_min=00:00m..23:59m; times=array(TIME, 0, 1440); for(m in times_min) times.append!(time(m)); times.append!(23:59:59.999); time_range=cutPoints(times, 240); 或者用下面代码: time_range=time(00:00m+0..239*6).append!(23:59:59.999)
回答于 2021-06-15 14:35
可以用下面代码所示方式: t=table([2,3,NULL,1] as v,[2010.01.01,2010.01.01,2010.01.03,2010.01.02] as dates) d1=2010.01.01 d2=2010.01.02 select * from t where dates between d1:d2
回答于 2021-06-15 14:30