MongoRecipes

JS

info

  db.version(); 
  db.stats();
  db.collection.stats();
  db.collection.storageSize()

Select where field type is string

  db.collection.find({field:{$type:2}})

Update ALL records with field

  db.collection.update(  
      { field: "old value" },  
      { $set: { field: "new value" } },  
      {upsert: 0, multi: 1} ) 

update schema rename column

  db.fs.files.update({}, {$rename: {'metadata.Height': 'metadata.height'}}, {multi:true});     
  db.fs.files.update({}, {$rename: {'metadata.Width': 'metadata.width'}}, {multi:true});  

Check field exists

  db.fs.files.find ({ "metadata": {$exists: true} }) 
  db.fs.files.count({ "metadata.creationTimeUtc": {$exists: false}}) 
  db.fs.files.count({ "metadata.Width": {$exists: true}, "metadata.Height": {$exists: true}}) 

capped collection with a tailable cursor
```
  db.createCollection("log", {capped:true, size:100000, max:5000}) /* { "ok" : 1 } */
  db.log.isCapped() /* true */
```
MongoDb C# driver CursorType enumeration. MongoDb C# driver wire protocol QueryMessage.TailableCursor. QueryMessage.AwaitData Gets a value indicating whether the server should await data (used with tailable cursors).

bulk insert

  var bulk = db.items.initializeUnorderedBulkOp(); 
  bulk.insert( { item: "abc123", defaultQty: 100, status: "A", points: 100 } ); 
  bulk.insert( { item: "ijk123", defaultQty: 200, status: "A", points: 200 } ); 
  bulk.insert( { item: "mop123", defaultQty: 0, status: "P", points: 0 } ); 
  bulk.execute();

rename database OldDb to DbNew

  db.copyDatabase("OldDb","DbNew","localhost") 
  use OldDb 
  db.dropDatabase();

db.collection.insertMany() new in 3.2

GridFS

removal

 db.fs.files.remove(); 
 db.getCollection('fs.chunks').remove();

Most recently updated / modified

  db.fs.files.find({filename :/.*.PNG.*/ }).sort({uploadDate:-1});
  db.fs.files.find({filename :/.*.JPG.*/ }).sort({"metadata.lastWriteTimeUtc":-1})

and caused me pain

  db.fs.files.count(); 
  db.fs.files.find({length :{"$gt": 0} }).sort({length:-1}); 
  db.fs.files.find({ uploadDate :{"$lt": ISODate("2015-12-15T00:00:00.000Z")} },{"_id":0,"filename":1, uploadDate:1}).sort({uploadDate:-1}).pretty()
  db.fs.files.distinct( "filename")

group by h x w, push filenames, count filenames in each group

  db.fs.files.aggregate([ 
      { $group: { 
          _id: { "w":"$metadata.width", "h":"$metadata.height" }, 
          files: { $push: "$filename" }, 
          no: { $sum: 1 } 
      } } 
  ])				``````````

old c# api v1
upload files 2.2, 2.4
Download files
Find files
Delete and rename

CLI

mongoexport docs, in pairs, export-import, dump-restore connect to powershell ps d:\mongodb\server\3.0\bin>
.\mongoexport -d imagesDB -c fs.files -o 10.11.11.45.fs.files.json .\mongoexport -d imagesDB -c fs.chunks -o 10.11.11.45.fs.chunks.json

Message: connected to: localhost; exported 115 records
mongoimport.exe –db ImageCache10111145 –collection fs.files –file 10.11.11.45.fs.files.json mongoimport.exe –db ImageCache10111145 –collection fs.chunks –file 10.11.11.45.fs.chunks.json

C#

driver releases
update
old driver cheat sheet
Query by a Field in an Embedded Document
distinct array subdocuments SO, api
Using a Tailable Cursor
Configure GridFS Chunksize in MongoDB, todo update
Mongo DB support for Hangfire sources
Building MongoDB Applications with Binary Files Using GridFS 1 and 2
Driver v1.11 install tutorial
Getting started with GridFS driver v2

cursor with filter

  using (var cursor = await FsFiles.FindAsync(filter)) { 
           while (cursor.MoveNext()) { 
               foreach (var bsonDoc in cursor.Current) {
                  // bsonDoc.DoSomething(); 
  } } }

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