fix(mongo) Change count_documents to estimated_document_count

[zhuatuzilo]

数据量较大时，使用count_documents 精确统计行数会影响到生产的负载，用estimated_document_count替换

[chatgpt-codex-connector]

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[RankRao]

count = db[table_name].count_documents({})
这一段是在get_table_conut函数（注：函数名应该改为正确英文get_table_count）中，
然后调用的是mongo的精确计数count()，其实在高版本mongo中已经不再推荐使用count()方法。

get_table_conut函数被调用的主要是两个地方：
1、创建索引，判断是否为大表，增加校验background:true。
2、drop, dropIndex, dropIndexes, createIndex, createIndexes, ensureIndex等方法，返回全表的影响行数。

可以考虑更优化下get_table_conut函数
如果
count = db[table_name].estimated_document_count({})
大于100万
直接返回count，
否则小表还是用精确计数
count = db[table_name].count_documents({})

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[zhuatuzilo]

count = db[table_name].count_documents({}) 这一段是在get_table_conut函数（注：函数名应该改为正确英文get_table_count）中， 然后调用的是mongo的精确计数count()，其实在高版本mongo中已经不再推荐使用count()方法。

get_table_conut函数被调用的主要是两个地方： 1、创建索引，判断是否为大表，增加校验background:true。 2、drop, dropIndex, dropIndexes, createIndex, createIndexes, ensureIndex等方法，返回全表的影响行数。

可以考虑更优化下get_table_conut函数 如果 count = db[table_name].estimated_document_count({}) 大于100万 直接返回count， 否则小表还是用精确计数 count = db[table_name].count_documents({})

有道理，我改下