: 0, "nModified" : 0 })
> db.array.find({},{'_id':0})
{ "age" : 65, "name" : "laoda", "phone" : [ 111, 222, 111, 222, [ 111, 222 ], 333 ] }
8.$pop 删除数组内的一个值
#删除最后一个值：{ $pop : { field : 1 } }删除第一个值：{ $pop : { field : -1 } }
注意，只能删除一个值，也就是说只能用1或-1，而不能用2或-2来删除两条
> db.array.find({},{'_id':0})
{ "age" : 65, "name" : "laoda", "phone" : [ 111, 222, 111, 222, [ 111, 222 ], 333 ] }
> db.array.update({'name':'laoda','age':65},{$pop:{"phone":1}})
WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 })
> db.array.find({},{'_id':0})
{ "age" : 65, "name" : "laoda", "phone" : [ 111, 222, 111, 222, [ 111, 222 ] ] }
> db.array.update({'name':'laoda','age':65},{$pop:{"phone":-1}})
WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 })
> db.array.find({},{'_id':0})
{ "age" : 65, "name" : "laoda", "phone" : [ 222, 111, 222, [ 111, 222 ] ] }
> db.array.update({'name':'laoda','age':65},{$pop:{"phone":2}})
WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 })
> db.array.find({},{'_id':0})
{ "age" : 65, "name" : "laoda", "phone" : [ 222, 111, 222 ] }
> db.array.update({'name':'laoda','age':65},{$pop:{"phone":333}})
WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 })
> db.array.find({},{'_id':0})
{ "age" : 65, "name" : "laoda", "phone" : [ 222, 111 ] }
> db.array.update({'name':'laoda','age':65},{$pop:{"phone":-333}})
WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 })
> db.array.find({},{'_id':0})
{ "age" : 65, "name" : "laoda", "phone" : [ 111 ] }
#测试发现，只要是正整数从最后删除，负数从头部删除。
9.$pull 数组field内删除一个等于value值
> db.array.find({},{'_id':0})
{ "age" : 65, "name" : "laoda", "phone" : [ 111, 333 ] }
> db.array.update({'name':'laoda','age':65},{$pull:{"phone":333}})
WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 })
> db.array.find({},{'_id':0})
{ "age" : 65, "name" : "laoda", "phone" : [ 111 ] }
10.$pullAll 数组field内删除多个值
> db.array.find({},{'_id':0})
{ "age" : 65, "name" : "laoda", "phone" : [ 111, 333, 222 ] }
> db.array.update({'name':'laoda','age':65},{$pullAll:{"phone":[111,222]}})
WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 })
> db.array.find({},{'_id':0})
{ "age" : 65, "name" : "laoda", "phone" : [ 333 ] }