----------1.复制数据库

wind:PRIMARY> show dbs;
jinri  0.078GB
local  1.078GB
test   0.078GB
wind   0.078GB

wind:PRIMARY> use admin;
switched to db admin


db.runCommand(
{copydb : 1,
fromhost : "localhost",
fromdb : "wind",
todb : "snow"
}
);

#执行结果
wind:PRIMARY> use admin;
switched to db admin

wind:PRIMARY> db.runCommand(
... {copydb : 1,
... fromhost : "localhost",
... fromdb : "wind",
... todb : "snow"
... }
... );
{ "ok" : 1 }
wind:PRIMARY> show dbs;
jinri  0.078GB
local  1.078GB
snow   0.078GB
test   0.078GB
wind   0.078GB
wind:PRIMARY> use snow;
switched to db snow
wind:PRIMARY> show tables;
system.indexes
tblorders


wind:PRIMARY> use snow;
switched to db snow
wind:PRIMARY> db.tblorders.find().count();
3


-------2.重命名集合

use admin;

db.runCommand(
{
renameCollection:"snow.tblorders",
to: "wind.tblbooks",
dropTarget: false
}
);


--case01:

wind:PRIMARY> use snow;
switched to db snow
wind:PRIMARY> show tables;
system.indexes
tblorders

wind:PRIMARY> use wind;
switched to db wind
wind:PRIMARY> show tables;
system.indexes
tblorders


wind:PRIMARY> use admin;
switched to db admin

wind:PRIMARY> 
wind:PRIMARY> db.runCommand(
... {
... renameCollection:"snow.tblorders",
... to: "wind.tblbooks",
... dropTarget: false
... }
... );
{ "ok" : 1 }
wind:PRIMARY> use snow;
switched to db snow
wind:PRIMARY> show tables;
system.indexes
wind:PRIMARY> use wind;
switched to db wind
wind:PRIMARY> show tables;
system.indexes
tblbooks
tblorders


--case02:


wind:PRIMARY> use wind;
switched to db wind
wind:PRIMARY> show tables;
system.indexes
tblbooks
tblorders
wind:PRIMARY> use snow;
switched to db snow
wind:PRIMARY> show tables;
system.indexes


use admin;

db.runCommand(
{
renameCollection:"wind.tblorders",
to: "snow.tblbooks",
dropTarget: true
}
);

wind:PRIMARY> use wind;
switched to db wind
wind:PRIMARY> show tables;
system.indexes
tblbooks
wind:PRIMARY> use snow;
switched to db snow
wind:PRIMARY> show tables;
system.indexes
tblbooks
wind:PRIMARY> use snow;
switched to db snow
wind:PRIMARY> show tables;
system.indexes
tblbooks


-------3.查看数据库和集合的统计信息

db.stats();

wind:PRIMARY> db.tblorders.stats();
{
	"ns" : "jinri.tblorders",
	"count" : 5,
	"size" : 560,
	"avgObjSize" : 112,
	"numExtents" : 1,
	"storageSize" : 8192,
	"lastExtentSize" : 8192,
	"paddingFactor" : 1,
	"paddingFactorNote" : "paddingFactor is unused and unmaintained in 3.0. It remains hard coded to 1.0 for compatibility only.",
	"userFlags" : 1,
	"capped" : false,
	"nindexes" : 1,
	"totalIndexSize" : 8176,
	"indexSizes" : {
		"_id_" : 8176
	},
	"ok" : 1
}


wind:PRIMARY> db.stats();
{
	"db" : "jinri",  #数据库名
	"collections" : 3, #collection的数量
	"objects" : 9,  #对象数据量
	"avgObjSize" : 90.66666666666667,  #对象平均大小
	"dataSize" : 816,  #数据大小
	"storageSize" : 20480,  #数据存储大小包括预分配空间
	"numExtents" : 3,  #事件数量
	"indexes" : 1,  #索引数量
	"indexSize" : 8176,  #索引大小
	"fileSize" : 67108864,  #文件大小
	"nsSizeMB" : 16,
	"extentFreeList" : {
		"num" : 0,
		"totalSize" : 0
	},
	"dataFileVersion" : {
		"major" : 4,
		"minor" : 22
	},
	"ok" : 1  #本次stats是否正常
}



---4.检查数据库

wind:PRIMA