1.索引类型为Date问题

"activitytime": {
   "type": "date",
   "format": "epoch_second"
}

报错：
message [ElasticsearchException[Elasticsearch exception [type=mapper_parsing_exception, reason=failed to parse field [activitytime] of type [date] in document with id "4689544955"]]; nested: ElasticsearchException[Elasticsearch exception [type=illegal_argument_exception, reason=Invalid format: ""]];]

Es原始数据：
"idx_facultyid" : "FacultyId_1006000",
"activitytime" : null,
"mainfacultyrank" : "2537",

本次更新数据：
"idx_facultyid" : "FacultyId_1006000",
"activitytime" : "",
"mainfacultyrank" : "2537"

解释：由于mapping的activitytime字段类型为date，当更新的数据为“”时，会报错。

总结：date类型的字段，禁止传""