collection.delete

This method can be used to delete a document from a collection. It accepts a json object which specifies the match condition and returns the count of total deleted documents. It accepts following arguments

Name	Type	Description
filter	object	a json object which specifies the match condition of documents

It is important to note here that running this function without specifying the match condition will result in deletion of all the documents of a collection.

This method returns following codes

DATA-INVALID

collection name wasn't specified while getting the reference

DATASTORE-DOCUMENTS-NOT-FOUND

not even a single document qualified the match condition so delete count is zero

DATASTORE-DOCUMENTS-DELETED

deleted the matched documents

DATASTORE-DOCUMENTS-DELETION-FAILED

failed to delete the documents

The usage of this method is illustrated in the example below

// This method can be used in many ways
 
// Case: delete a specific document by providing
// the document id, you can use this on other 
// attributes as well
collection.delete({documentID: "id"}).then((res) => {
  // Got response from server
  switch(res.code) {
    case "DATASTORE-DOCUMENTS-DELETED": 
      // Method returns the count
      // should be exactly 1 here
      console.log(res.deletedCount);
  }
});
 
// Case: delete multiple but specific documents
// Define an array of ids of documents required to
// be deleted, you can use this on other 
// attributes as well
var documentIDs = ["1", "2", "3"];
 
// Run operation with $in operator
collection.delete({documentID: {$in: documentIDs}}).then((res) => {
  // Got response from server
  switch(res.code) {
    case "DATASTORE-DOCUMENTS-DELETED": 
      // Method returns the count
      // should match the length of the array
      console.log(res.deletedCount);
  }
});
 
// Case: delete in range
// Run operation with $lt and $gt operator on attributes
collection.delete({voltage: {$lt: 25, $gt: 30}}).then((res) => {
  // Got response from server
  switch(res.code) {
    case "DATASTORE-DOCUMENTS-DELETED": 
      // Method returns the count
      console.log(res.deletedCount);
  }
});
 
// Case: delete all
// Run operation with $in operator
collection.delete().then((res) => {
  // Got response from server
  switch(res.code) {
    case "DATASTORE-DOCUMENTS-DELETED": 
      // Method returns the count
      console.log(res.deletedCount);
  }
});

.insert().search()