select*from postWHERE ip ! = 2130706433AND ip ! = 0AND ip ! = 2139062143AND ip ! = 127AND (ip < 2130706432 || ip > 2147483647)AND (ip < 167772160 || ip > 184549375)AND (valid = 1)The array I used is this$criteria = array(‘valid’=>1,‘ip’ => array(array(‘$nin’ => array(2130706433,0,127,2139062143)),array(‘$or’ => array(array(‘$gt’ => 2147483647), array(‘$lt’ => 2130706432)))array(‘$or’ => array(array(‘$gt’ ..
Category : question
Recently, I studied MongoDB and found some materials and books on the internet. I found that most of them are basic and not too deep. Especially, the use of MapReduce and Aggregation Pipeline is even less. As for MongoDB’s strong query support, it is still unclear where it is embodied. Kneel down and ask each ..
At present, there is a mongo service in the external network, which records logs every day. however, with the accumulation of time, the data logs in the external network become larger and larger. Now I want to synchronize the mongo log of the external network to the internal network in real time (here for example). ..
MongoDB database created a lot of data during the local previous test. Today it was opened and found that all the data disappeared.The previous IP address is different from the current IP address. The database is created on the local computer and then tested by computer link Do you want to ask whether the disappearance ..
1. The following data are available I want to sort in descending order according to the size of the content array. It means that the line’ general worker/operator’ is at the front and the line’ numerical control programming’ is at the back. I used it.sort({‘this.content.length’:-1})Andsort({‘content.$size’:-1})It turned out to be no good. It is possible to ..
db.getCollection(‘diseases’).find({}) db.diseases.find({}) There is no difference. However, if the collection name contains special characters, only the first method can be used.Special characters are not recommended for collect..
Problem description mongodb log: 2019-05-03T15:57:05.627+0800 I STORAGE [conn2] createCollection: test.site_userid_31917 with generated UUID: a7deb9ff-dfa5-4272-b10d-2da69c7a2e3c 2019-05-03T15:57:05.653+0800 I STORAGE [conn2] createCollection: test.site_userid_31918 with generated UUID: 8ae5dfdc-c416-482e-be28-ac0af623a512 2019-05-03T15:57:06.016+0800 E – [ftdc] Assertion: Location13538: couldn’t open [/proc/7276/stat] Unknown error src/mongo/util/processinfo_linux.cpp 81 2019-05-03T15:57:06.172+0800 E STORAGE [conn2] WiredTiger error (24) [1556870226:172133][7276:0x7f135e8b7700], WT_SESSION.create: __posix_directory_sync, 145: /var/lib/mongodb/: directory-sync: open: Too many open files ..
Is this starting? Mongo is still not a recognizable command. Is this starting? This is the start Mongo is still not a recognizable command. This is a question of how to use Windows. The command PATH needs to be added to the PATH variable of the system or executed in the directory where mongo is ..
Background: deployd and angular are currently working on a news website, which requires that only articles (including articles and pictures) can be added within the company. Because people who do not know the code are required to add articles, it is considered to use rich text as a background management system, and then the front ..
The code is as follows: user.find({ username }, { age: 1, _id: 0 }).toArray((err, doc) => { if (err) throw err; res.send(doc); }); The result was a return:[{“_id”:”5cbe59baaf2c3739490fd056″,”username”:”zjr”,”age”:19}], instead of returning only the age field as set above,That is to say, this way of writing does not correctly restrict fields.. My current solution is to ..
For example, I have a message table that stores messages. There are 1 million data stored every month, and there are tens of millions of messages in a year.Moreover, it is often necessary to query the data in the message table.Now the more data there is, the slower it will be and the server CPU ..
Business background I want to sort by time. Take the latest data Difficulties encountered March 2019 is always larger than April 2019 But normally, shouldn’t March be smaller than April? Sample code Ascending query > db.getCollection(“cash-infos”).find({},{createdAt:1}).sort({createdAt: 1}) {“_ id”: objectid (“5caa78992f26e525a86085d2”), “createdat”: “monapr08201906: 23: 46 gmt+0800 (china standard time)”} {“_ id”: objectid (“5caa80e83de 43925c80353a7”), “createdat”: ..