我是 WSO2 DAS 的新手。根据文件，它说DAS可以快速分析数据。我想举个例子。我的场景如下所示。
@Import('in_test_stream:1.0.0')
define stream inStream (a string, b string); *---> receive data*
@Export('out_other_stream:1.0.0')
define stream outOtherStream (a int);
@Export('out_test_stream:1.0.0')
define stream outStream (a string, b string, c string);
define table tmpTable (a long, b long, reg_date string);--> define meomry table for faster analytics
@info(name='query1') *---> loading incoming data into memory table.*
from inStream
select convert(a, 'long') as a, convert(b, 'long') as b, time:currentTimestamp() as reg_date
insert into tmpTable;
@info(name='query2') *--> maintain some number of data....the others will be delete....*
from inStream
delete tmpTable
on time:timestampInMilliseconds(tmpTable.reg_date, 'yyyy-MM-dd HH:mm:ss') < time:timestampInMilliseconds(time:dateSub(time:currentTimestamp(), 1, 'day', 'yyyy-MM-dd HH:mm:ss'), 'yyyy-MM-dd HH:mm:ss');
@info(name='query3')--> This is kind of analyzing data and push it to output...
from inStream as k1 join tmpTable as k2
select convert(stddev(k2.a), 'string') as a, convert(count(k2.b), 'string') as b, k2.reg_date as c
insert into outStream;
我制定了一个类似上面的解释计划。问题是 tmpTable 可能不会加载太多数据。我认为它应该加载大量数据。我的服务器有足够的内存。
请帮我。