Details
-
New Feature
-
Status: Closed
-
Major
-
Resolution: Won't Fix
-
v1.4.0
-
None
-
None
Description
TopN should support not only SUM, but also MAX, MIN as the expression.
A possible case is, find out the sellers which sold the top expensive items:
select seller_id, max(price) from sals_records where region = 'US' and year = '2015' order by max(price) desc limit 100;
In the future, more parameter should be supported
1) the expression (default SUM); 2) the soring order (default Desc). 3) the encoding method:
A sample is:
{
"name" : "TOP_SELLER",
"function" : {
"expression" : "TOP_N",
"parameter" : {
"id": 0,
"type" : "column",
"value" : "PRICE",
"next_parameter" : {
"id": 1,
"type" : "column",
"value" : "SELLER_ID",
"next_parameter" : {
"id": 2,
"type" : "",
"value" : "SUM",
"next_parameter" : {
"id": 3,
"type" : "",
"value" : "DESC"
"next_parameter" : {
"id": 4,
"type" : "",
"value" : "dict"
}
}
}
},
"returntype" : "topn(100)"
},