39_深入聚合数据分析_实战date hitogram之统计每月电视销量
bucket,分组操作,histogram,按照某个值指定的interval,划分一个一个的bucket
date histogram,按照我们指定的某个date类型的日期field,以及日期interval,按照一定的日期间隔,去划分bucket
date interval = 1m,
2017-01-01~2017-01-31,就是一个bucket
2017-02-01~2017-02-28,就是一个bucket
然后会去扫描每个数据的date field,判断date落在哪个bucket中,就将其放入那个bucket
2017-01-05,就将其放入2017-01-01~2017-01-31,就是一个bucket
min_doc_count:即使某个日期interval,2017-01-01~2017-01-31中,一条数据都没有,那么这个区间也是要返回的,不然默认是会过滤掉这个区间的
extended_bounds,min,max:划分bucket的时候,会限定在这个起始日期,和截止日期内
GET /tvs/sales/_search
{
"size" : 0,
"aggs": {
"sales": {
"date_histogram": {
"field": "sold_date",
"interval": "month",
"format": "yyyy-MM-dd",
"min_doc_count" : 0,
"extended_bounds" : {
"min" : "2016-01-01",
"max" : "2017-12-31"
}
}
}
}
}
搜索结果
{
"took": 16,
"timed_out": false,
"_shards": {
"total": 5,
"successful": 5,
"failed": 0
},
"hits": {
"total": 8,
"max_score": 0,
"hits": []
},
"aggregations": {
"group_by_sold_date": {
"buckets": [
{
"key_as_string": "2016-01-01",
"key": 1451606400000,
"doc_count": 0
},
{
"key_as_string": "2016-02-01",
"key": 1454284800000,
"doc_count": 0
},
{
"key_as_string": "2016-03-01",
"key": 1456790400000,
"doc_count": 0
},
{
"key_as_string": "2016-04-01",
"key": 1459468800000,
"doc_count": 0
},
{
"key_as_string": "2016-05-01",
"key": 1462060800000,
"doc_count": 1
},
{
"key_as_string": "2016-06-01",
"key": 1464739200000,
"doc_count": 0
},
{
"key_as_string": "2016-07-01",
"key": 1467331200000,
"doc_count": 1
},
{
"key_as_strin
"key_as_string": "2016-09-01",
"key": 1472688000000,
"doc_count": 0
},g": "2016-08-01",
"key": 1470009600000,
"doc_count": 1
},
{
{
"key_as_string": "2016-10-01",
"key": 1475280000000,
"doc_count": 1
},
{
"key_as_string": "2016-11-01",
"key": 1477958400000,
"doc_count": 2
},
{
"key_as_string": "2016-12-01",
"key": 1480550400000,
"doc_count": 0
},
{
"key_as_string": "2017-01-01",
"key": 1483228800000,
"doc_count": 1
},
{
"key_as_string": "2017-02-01",
"key": 1485907200000,
"doc_count": 1
}
]
}
}
}