db.collection.stats()
在本页面
db.collection.stats(选项)
返回有关集合的统计信息。
该方法包括以下参数：
参数 | 类型 | 描述 |
|---|---|---|
scale | number | 可选的。输出中使用的比例显示项目的大小。默认情况下，输出显示 bytes中的大小。要显示千字节而不是字节，请指定1024 value 1024。 如果您指定非整数比例因子，则MongoDB将使用指定因子的整数部 分。例如，如果将比例因子指定为1023.999，则MongoDB将使用1023该比例因子。 从4.2版开始，输出包括scaleFactor 用于缩放大小值的输出。 |
indexDetails | boolean | 可选的。如果为 true，则db.collection.stats()除收集统计信息外，还返回 index details 仅适用于WiredTiger存储引擎。 默认为false。 |
indexDetailsKey | document | 可选的。如果 indexDetails是true，则可以使用indexDetailsKey通过指定索引 key 规范来过滤索引详细信息。只返回与indexDetailsKey完全匹配的索引。 如果找不到匹配项，indexDetails将显示所有索引的统计信息。 使用getIndexes()发现索引键。你不能将indexDetailsKey与indexDetailsName一起使用。 |
indexDetailsName | string | 可选的。如果 indexDetails是true，则可以使用indexDetailsName通过指定索引name来过滤索引详细信息。只返回与indexDetailsName完全匹配的索引名称。 如果找不到匹配项，indexDetails将显示所有索引的统计信息。 使用getIndexes()来发现索引名称。你不能将indexDetailsName与indexDetailsField一起使用。 |
仅指定
scale因素，MongoDB支持旧格式：db.collection.stats(<number>)
返回值： | 包含有关指定集合的统计信息的文档。请参阅 collStats以获取返回统计信息的细分。 |
该
db.collection.stats()方法提供了围绕数据库命令的包装collStats。除非度量标准名称（例如
"bytes currently in the cache" ）另外指定，与大小相关的值以字节为单位显示，可以按比例覆盖。比例因子将受影响的大小值四舍五入为整数。
根据存储引擎，返回的数据可能不同。有关字段的详细信息，请参阅输出详细信息。
使用Wired Tiger存储引擎不正常关闭mongod后，db.collection.stats()报告的计数和大小统计信息可能不准确。
偏移量取决于在最后检查站和不干净关闭之间执行的 insert，update 或 delete 操作的数量。检查点通常每 60 秒发生一次。但是，使用 non-default --syncdelay设置运行mongod实例可能会有更多或更少的检查点。
在mongod上的每个集合上运行验证以在不正常关闭后恢复正确的统计信息。
使用
indexDetailsKey或indexDetailsName过滤indexDetails将仅_return 单个匹配的索引。如果未找到确切的 match，indexDetails将显示有关集合的所有索引的信息。indexDetailsKey字段采用以下形式的文档：{ '<string>' : <value>, '<string>' : <value>, ... }
其中
<string>是索引的字段，<value>是索引的方向，或特殊索引类型，如text或2dsphere。有关索引类型的完整列表，请参见索引类型。对于使用WiredTiger存储引擎的 MongoDB 实例，在不正常关闭后，大小和计数的统计信息可能会被collStats，dbStats，计数报告最多 1000 个文档。要恢复集合的正确统计信息，请在集合上运行 run 验证。
从MongoDB 4.2开始，
db.collection.stats包括有关当前正在构建的索引的信息。有关详细信息，请参见：collStats.nindexescollStats.indexDetailscollStats.indexBuildscollStats.totalIndexSizecollStats.indexSizes
注意您可以在入门指南中找到用于这些示例的集合数据
以下操作返回
restaurants集合上的统计信息 ：db.restaurants.stats()
操作返回：
{
"ns" : "guidebook.restaurants",
"count" : 25359,
"size" : 10630398,
"avgObjSize" : 419,
"storageSize" : 4104192
"capped" : false,
"wiredTiger" : {
"metadata" : {
"formatVersion" : 1
},
"creationString" : "allocation_size=4KB,app_metadata=(formatVersion=1),block_allocation=best,block_compressor=snappy,cache_resident=0,checksum=on,colgroups=,collator=,columns=,dictionary=0,encryption=(keyid=,name=),exclusive=0,extractor=,format=btree,huffman_key=,huffman_value=,immutable=0,internal_item_max=0,internal_key_max=0,internal_key_truncate=,internal_page_max=4KB,key_format=q,key_gap=10,leaf_item_max=0,leaf_key_max=0,leaf_page_max=32KB,leaf_value_max=64MB,log=(enabled=),lsm=(auto_throttle=,bloom=,bloom_bit_count=16,bloom_config=,bloom_hash_count=8,bloom_oldest=0,chunk_count_limit=0,chunk_max=5GB,chunk_size=10MB,merge_max=15,merge_min=0),memory_page_max=10m,os_cache_dirty_max=0,os_cache_max=0,prefix_compression=0,prefix_compression_min=4,source=,split_deepen_min_child=0,split_deepen_per_child=0,split_pct=90,type=file,value_format=u",
"type" : "file",
"uri" : "statistics:table:collection-2-7253336746667145592",
"LSM" : {
"bloom filters in the LSM tree" : 0,
"bloom filter false positives" : 0,
"bloom filter hits" : 0,
"bloom filter misses" : 0,
"bloom filter pages evicted from cache" : 0,
"bloom filter pages read into cache" : 0,
"total size of bloom filters" : 0,
"sleep for LSM checkpoint throttle" : 0,
"chunks in the LSM tree" : 0,
"highest merge generation in the LSM tree" : 0,
"queries that could have benefited from a Bloom filter that did not exist" : 0,
"sleep for LSM merge throttle" : 0
},
"block-manager" : {
"file allocation unit size" : 4096,
"blocks allocated" : 338,
"checkpoint size" : 4096000,
"allocations requiring file extension" : 338,
"blocks freed" : 0,
"file magic number" : 120897,
"file major version number" : 1,
"minor version number" : 0,
"file bytes available for reuse" : 0,
"file size in bytes" : 4104192
},
"btree" : {
"btree checkpoint generation" : 15,
"column-store variable-size deleted values" : 0,
"column-store fixed-size leaf pages" : 0,
"column-store internal pages" : 0,
"column-store variable-size leaf pages" : 0,
"pages rewritten by compaction" : 0,
"number of key/value pairs" : 0,
"fixed-record size" : 0,
"maximum tree depth" : 3,
"maximum internal page key size" : 368,
"maximum internal page size" : 4096,
"maximum leaf page key size" : 3276,
"maximum leaf page size" : 32768,
"maximum leaf page value size" : 67108864,
"overflow pages" : 0,
"row-store internal pages" : 0,
"row-store leaf pages" : 0
},
"cache" : {
"bytes read into cache" : 9309503,
"bytes written from cache" : 10817368,
"checkpoint blocked page eviction" : 0,
"unmodified pages evicted" : 0,
"page split during eviction deepened the tree" : 0,
"modified pages evicted" : 1,
"data source pages selected for eviction unable to be evicted" : 0,
"hazard pointer blocked page eviction" : 0,
"internal pages evicted" : 0,
"pages split during eviction" : 1,
"in-memory page splits" : 1,
"overflow values cached in memory" : 0,
"pages read into cache" : 287,
"overflow pages read into cache" : 0,
"pages written from cache" : 337
},
"compression" : {
"raw compression call failed, no additional data available" : 0,
"raw compression call failed, additional data available" : 0,
"raw compression call succeeded" : 0,
"compressed pages read" : 287,
"compressed pages written" : 333,
"page written failed to compress" : 0,
"page written was too small to compress" : 4
},
"cursor" : {
"create calls" : 1,
"insert calls" : 25359,
"bulk-loaded cursor-insert calls" : 0,
"cursor-insert key and value bytes inserted" : 10697901,
"next calls" : 76085,
"prev calls" : 1,
"remove calls" : 0,
"cursor-remove key bytes removed" : 0,
"reset calls" : 25959,
"restarted searches" : 0,
"search calls" : 0,
"search near calls" : 594,
"update calls" : 0,
"cursor-update value bytes updated" : 0
},
"reconciliation" : {
"dictionary matches" : 0,
"internal page multi-block writes" : 1,
"leaf page multi-block writes" : 2,
"maximum blocks required for a page" : 47,
"internal-page overflow keys" : 0,
"leaf-page overflow keys" : 0,
"overflow values written" : 0,
"pages deleted" : 0,
"page checksum matches" : 0,
"page reconciliation calls" : 4,
"page reconciliation calls for eviction" : 1,
"leaf page key bytes discarded using prefix compression" : 0,
"internal page key bytes discarded using suffix compression" : 333
},
"session" : {
"object compaction" : 0,
"open cursor count" : 1
},
"transaction" : {
"update conflicts" : 0
}
},
"nindexes" : 4,
"totalIndexSize" : 626688,
"indexSizes" : {
"_id_" : 217088,
"borough_1_cuisine_1" : 139264,
"cuisine_1" : 131072,
"borough_1_address.zipcode_1" : 139264
},
"ok" : 1
}
由于统计数据未给出比例参数，因此所有大小值都在
bytes中。以下操作通过指定
scale的scale来更改从bytes到kilobytes的数据比例：db.restaurants.stats( { scale : 1024 } )
操作返回：
{
"ns" : "guidebook.restaurants",
"count" : 25359,
"size" : 10381,
"avgObjSize" : 419,
"storageSize" : 4008,
"capped" : false,
"wiredTiger" : {
...
},
"nindexes" : 4,
"totalIndexSize" : 612,
"indexSizes" : {
"_id_" : 212,
"borough_1_cuisine_1" : 136,
"cuisine_1" : 128,
"borough_1_address.zipcode_1" : 136
},
"ok" : 1
}
以下操作将创建一个
indexDetails文档，其中包含与集合中每个索引相关的信息：db.restaurant.stats( { indexDetails : true } )
操作返回：
{
"ns" : "guidebook.restaurants",
"count" : 25359,
"size" : 10630398,
"avgObjSize" : 419,
"storageSize" : 4104192,
"capped" : false,
"wiredTiger" : {
...
},
"nindexes" : 4,
"indexDetails" : {
"_id_" : {
"metadata" : {
"formatVersion" : 6,
"infoObj" : "{ "v" : 1, "key" : { "_id" : 1 }, "name" : "_id_", "ns" : "blogs.posts" }"
},
"creationString" : "allocation_size=4KB,app_metadata=(formatVersion=6,infoObj={ "v" : 1, "key" : { "_id" : 1 }, "name" : "_id_", "ns" : "blogs.posts" }),block_allocation=best,block_compressor=,cache_resident=0,checksum=on,colgroups=,collator=,columns=,dictionary=0,encryption=(keyid=,name=),exclusive=0,extractor=,format=btree,huffman_key=,huffman_value=,immutable=0,internal_item_max=0,internal_key_max=0,internal_key_truncate=,internal_page_max=16k,key_format=u,key_gap=10,leaf_item_max=0,leaf_key_max=0,leaf_page_max=16k,leaf_value_max=0,log=(enabled=),lsm=(auto_throttle=,bloom=,bloom_bit_count=16,bloom_config=,bloom_hash_count=8,bloom_oldest=0,chunk_count_limit=0,chunk_max=5GB,chunk_size=10MB,merge_max=15,merge_min=0),memory_page_max=5MB,os_cache_dirty_max=0,os_cache_max=0,prefix_compression=true,prefix_compression_min=4,source=,split_deepen_min_child=0,split_deepen_per_child=0,split_pct=75,type=file,value_format=u",
"type" : "file",
"uri" : "statistics:table:index-3-7253336746667145592",
"LSM" : {
...
},
"block-manager" : {
...
},
"btree" : {
...
},
"cache" : {
...
},
"compression" : {
...
},
"cursor" : {
...
},
"reconciliation" : {
...
},
"session" : {
...
},
"transaction" : {
...
}
},
"borough_1_cuisine_1" : {
"metadata" : {
"formatVersion" : 6,
"infoObj" : "{ "v" : 1, "key" : { "borough" : 1, "cuisine" : 1 }, "name" : "borough_1_cuisine_1", "ns" : "blogs.posts" }"
},
"creationString" : "allocation_size=4KB,app_metadata=(formatVersion=6,infoObj={ "v" : 1, "key" : { "borough" : 1, "cuisine" : 1 }, "name" : "borough_1_cuisine_1", "ns" : "blogs.posts" }),block_allocation=best,block_compressor=,cache_resident=0,checksum=on,colgroups=,collator=,columns=,dictionary=0,encryption=(keyid=,name=),exclusive=0,extractor=,format=btree,huffman_key=,huffman_value=,immutable=0,internal_item_max=0,internal_key_max=0,internal_key_truncate=,internal_page_max=16k,key_format=u,key_gap=10,leaf_item_max=0,leaf_key_max=0,leaf_page_max=16k,leaf_value_max=0,log=(enabled=),lsm=(auto_throttle=,bloom=,bloom_bit_count=16,bloom_config=,bloom_hash_count=8,bloom_oldest=0,chunk_count_limit=0,chunk_max=5GB,chunk_size=10MB,merge_max=15,merge_min=0),memory_page_max=5MB,os_cache_dirty_max=0,os_cache_max=0,prefix_compression=true,prefix_compression_min=4,source=,split_deepen_min_child=0,split_deepen_per_child=0,split_pct=75,type=file,value_format=u",
"type" : "file",
"uri" : "statistics:table:index-4-7253336746667145592",
"LSM" : {
...
},
"block-manager" : {
...
},
"btree" : {
...
},
"cache" : {
...
},
"compression" : {
...
},
"cursor" : {
...
},
"reconciliation" : {
...
},
"session" : {
"object compaction" : 0,
"open cursor count" : 0
},
"transaction" : {
"update conflicts" : 0
}
},
"cuisine_1" : {
"metadata" : {
"formatVersion" : 6,
"infoObj" : "{ "v" : 1, "key" : { "cuisine" : 1 }, "name" : "cuisine_1", "ns" : "blogs.posts" }"
},
"creationString" : "allocation_size=4KB,app_metadata=(formatVersion=6,infoObj={ "v" : 1, "key" : { "cuisine" : 1 }, "name" : "cuisine_1", "ns" : "blogs.posts" }),block_allocation=best,block_compressor=,cache_resident=0,checksum=on,colgroups=,collator=,columns=,dictionary=0,encryption=(keyid=,name=),exclusive=0,extractor=,format=btree,huffman_key=,huffman_value=,immutable=0,internal_item_max=0,internal_key_max=0,internal_key_truncate=,internal_page_max=16k,key_format=u,key_gap=10,leaf_item_max=0,leaf_key_max=0,leaf_page_max=16k,leaf_value_max=0,log=(enabled=),lsm=(auto_throttle=,bloom=,bloom_bit_count=16,bloom_config=,bloom_hash_count=8,bloom_oldest=0,chunk_count_limit=0,chunk_max=5GB,chunk_size=10MB,merge_max=15,merge_min=0),memory_page_max=5MB,os_cache_dirty_max=0,os_cache_max=0,prefix_compression=true,prefix_compression_min=4,source=,split_deepen_min_child=0,split_deepen_per_child=0,split_pct=75,type=file,value_format=u",
"type" : "file",
"uri" : "statistics:table:index-5-7253336746667145592",
"LSM" : {
...
},
"block-manager" : {
...
},
"btree" : {
...
},
"cache" : {
...
},
"compression" : {
...
},
"cursor" : {
...
},
"reconciliation" : {
...
},
"session" : {
...
},
"transaction" : {
...
}
},
"borough_1_address.zipcode_1" : {
"metadata" : {
"formatVersion" : 6,
"infoObj" : "{ "v" : 1, "key" : { "borough" : 1, "address.zipcode" : 1 }, "name" : "borough_1_address.zipcode_1", "ns" : "blogs.posts" }"
},
"creationString" : "allocation_size=4KB,app_metadata=(formatVersion=6,infoObj={ "v" : 1, "key" : { "borough" : 1, "address.zipcode" : 1 }, "name" : "borough_1_address.zipcode_1", "ns" : "blogs.posts" }),block_allocation=best,block_compressor=,cache_resident=0,checksum=on,colgroups=,collator=,columns=,dictionary=0,encryption=(keyid=,name=),exclusive=0,extractor=,format=btree,huffman_key=,huffman_value=,immutable=0,internal_item_max=0,internal_key_max=0,internal_key_truncate=,internal_page_max=16k,key_format=u,key_gap=10,leaf_item_max=0,leaf_key_max=0,leaf_page_max=16k,leaf_value_max=0,log=(enabled=),lsm=(auto_throttle=,bloom=,bloom_bit_count=16,bloom_config=,bloom_hash_count=8,bloom_oldest=0,chunk_count_limit=0,chunk_max=5GB,chunk_size=10MB,merge_max=15,merge_min=0),memory_page_max=5MB,os_cache_dirty_max=0,os_cache_max=0,prefix_compression=true,prefix_compression_min=4,source=,split_deepen_min_child=0,split_deepen_per_child=0,split_pct=75,type=file,value_format=u",
"type" : "file",
"uri" : "statistics:table:index-6-7253336746667145592",
"LSM" : {
...
},
"block-manager" : {
...
},
"btree" : {
...
},
"cache" : {
...
},
"compression" : {
...
},
"cursor" : {
...
},
"reconciliation" : {
...
},
"session" : {
...
},
"transaction" : {
...
}
}
},
"totalIndexSize" : 626688,
"indexSizes" : {
"_id_" : 217088,
"borough_1_cuisine_1" : 139264,
"cuisine_1" : 131072,
"borough_1_address.zipcode_1" : 139264
},
"ok" : 1
}
要过滤indexDetails字段中的索引，可以使用
indexDetailsKey选项指定索引键，也可以使用indexDetailsName指定索引 name。要发现集合的索引键和名称，请使用db.collection.getIndexes()。给定以下索引：
{
"ns" : "guidebook.restaurants",
"v" : 1,
"key" : {
"borough" : 1,
"cuisine" : 1
},
"name" : "borough_1_cuisine_1"
}
以下操作将
indexDetails文档过滤为indexDetailsKey文档定义的单个索引。db.restaurants.stats(
{
'indexDetails' : true,
'indexDetailsKey' :
{
'borough' : 1,
'cuisine' : 1
}
}
)
以下操作将
indexDetails文档过滤为indexDetailsName文档定义的单个索引。db.restaurants.stats(
{
'indexDetails' : true,
'indexDetailsName' : 'borough_1_cuisine_1'
}
)
两个操作都会 return 相同的输出：
{
"ns" : "blogs.restaurants",
"count" : 25359,
"size" : 10630398,
"avgObjSize" : 419,
"storageSize" : 4104192,
"capped" : false,
"wiredTiger" : {
...
},
"nindexes" : 4,
"indexDetails" : {
"borough_1_cuisine_1" : {
"metadata" : {
"formatVersion" : 6,
"infoObj" : "{ "v" : 1, "key" : { "borough" : 1, "cuisine" : 1 }, "name" : "borough_1_cuisine_1", "ns" : "blogs.posts" }"
},
"creationString" : "allocation_size=4KB,app_metadata=(formatVersion=6,infoObj={ "v" : 1, "key" : { "borough" : 1, "cuisine" : 1 }, "name" : "borough_1_cuisine_1", "ns" : "blogs.posts" }),block_allocation=best,block_compressor=,cache_resident=0,checksum=on,colgroups=,collator=,columns=,dictionary=0,encryption=(keyid=,name=),exclusive=0,extractor=,format=btree,huffman_key=,huffman_value=,immutable=0,internal_item_max=0,internal_key_max=0,internal_key_truncate=,internal_page_max=16k,key_format=u,key_gap=10,leaf_item_max=0,leaf_key_max=0,leaf_page_max=16k,leaf_value_max=0,log=(enabled=),lsm=(auto_throttle=,bloom=,bloom_bit_count=16,bloom_config=,bloom_hash_count=8,bloom_oldest=0,chunk_count_limit=0,chunk_max=5GB,chunk_size=10MB,merge_max=15,merge_min=0),memory_page_max=5MB,os_cache_dirty_max=0,os_cache_max=0,prefix_compression=true,prefix_compression_min=4,source=,split_deepen_min_child=0,split_deepen_per_child=0,split_pct=75,type=file,value_format=u",
"type" : "file",
"uri" : "statistics:table:index-4-7253336746667145592",
"LSM" : {
...
},
"block-manager" : {
...
},
"btree" : {
...
},
"cache" : {
...
},
"compression" : {
...
},
"cursor" : {
...
},
"reconciliation" : {
...
},
"session" : {
...
},
"transaction" : {
...
}
}
},
"totalIndexSize" : 626688,
"indexSizes" : {
"_id_" : 217088,
"borough_1_cuisine_1" : 139264,
"cuisine_1" : 131072,
"borough_1_address.zipcode_1" : 139264
},
"ok" : 1
}
有关输出的说明，请参阅输出细节。
也可以看看$collStats
译者：李冠飞
校对：