下面是把title进行聚合，我想求聚合后桶的个数（不使用cardinality）
{
size:0,
"aggs": {
"unique_title": {
"terms": {
"field": "title",
"size": 10
}
}
}
}
https://www.cnblogs.com/bonelee/p/6344688.html
可以用cardinality去重
{
size:0,
"aggs": {
"unique_title": {
"cardinality": {
"field": "title"
}
}
}
}