Question

How to Fetch a batch of documents in pouchDB?

Answer 1

db.allDocs([options], [callback])

Fetch multiple documents, indexed and sorted by the _id. Deleted documents are only included if options.keys is specified.

Options

All options default to false unless otherwise specified.

• options.include_docs: Include the document itself in each row in the doc field. Otherwise by default you only get the _id and _rev properties.
• options.conflicts: Include conflict information in the _conflicts field of a doc.
• options.attachments: Include attachment data as base64-encoded string.
• options.binary: Return attachment data as Blobs/Buffers, instead of as base64-encoded strings.
• options.startkey & options.endkey: Get documents with IDs in a certain range (inclusive/inclusive).
• options.inclusive_end: Include documents having an ID equal to the given options.endkey. Default: true.
• options.limit: Maximum number of documents to return.
• options.skip: Number of docs to skip before returning (warning: poor performance on IndexedDB/LevelDB!).
• options.descending: Reverse the order of the output documents. Note that the order of startkey and endkey is reversed when descending:true.
• options.key: Only return documents with IDs matching this string key.
• options.keys: Array of string keys to fetch in a single shot.
  • Neither startkey nor endkey can be specified with this option.
  • The rows are returned in the same order as the supplied keys array.
  • The row for a deleted document will have the revision ID of the deletion, and an extra key "deleted":true in the value property.
  • The row for a nonexistent document will just contain an "error" property with the value "not_found".
  • For details, see the CouchDB query options documentation.
• options.update_seq: Include an update_seq value indicating which sequence id of the underlying database the view reflects.

Notes: For pagination, options.limit and options.skip are also available, but the same performance concerns as in CouchDB apply. Use the startkey/endkey pattern instead.

Example Usage

        Async functions

• Promises
• Callbacks

db.allDocs({
  include_docs: true,
  attachments: true
}).then(function (result) {
  // handle result
}).catch(function (err) {
  console.log(err);
);Example Response:

{
  "offset": 0,
  "total_rows": 1,
  "rows": [{
    "doc": {
      "_id": "0B3358C1-BA4B-4186-8795-9024203EB7DD",
      "_rev": "1-5782E71F1E4BF698FA3793D9D5A96393",
      "title": "Sound and Vision",
      "_attachments": {
      	"attachment/its-id": {
      	  "content_type": "image/jpg",
      	  "data": "R0lGODlhAQABAIAAAP7//wAAACH5BAAAAAAALAAAAAABAAEAAAICRAEAOw==",
      	  "digest": "md5-57e396baedfe1a034590339082b9abce"
      	}
      }
    },
   "id": "0B3358C1-BA4B-4186-8795-9024203EB7DD",
   "key": "0B3358C1-BA4B-4186-8795-9024203EB7DD",
   "value": {
    "rev": "1-5782E71F1E4BF698FA3793D9D5A96393"
   }
 }]
}

In the response, you have three things:

• total_rows the total number of non-deleted documents in the database
• offset the skip if provided, or in CouchDB the actual offset

• rows: rows containing the documents, or just the _id/_revs if you didn’t set include_docs to true.

• You may optionally also have update_seq if you set update_seq to true

You can use startkey/endkey to find all docs in a range:

• Async functions
• Promises
• Callbacks

db.allDocs({
  include_docs: true,
  attachments: true,
  startkey: 'bar',
  endkey: 'quux'
}).then(function (result) {
  // handle result
}).catch(function (err) {
  console.log(err);
});

This will return all docs with _ids between 'bar' and 'quux'.

Prefix search

You can do prefix search in allDocs() – i.e. “give me all the documents whose _ids start with 'foo'” – by using the special high Unicode character '\ufff0':

• Async functions
• Promises
• Callbacks

db.allDocs({
  include_docs: true,
  attachments: true,
  startkey: 'foo',
  endkey: 'foo\ufff0'
}).then(function (result) {
  // handle result
}).catch(</s