Returning documents: Difference between revisions
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Convert py3 -> mongo |
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{{TopTenTips}} | {{TopTenTips}} | ||
<div style='height:25em;'> | <div style='height:25em;'> | ||
</div> | </div> | ||
<div class=q data-lang=" | <div class="q" data-lang="mongo">Return all documents | ||
<pre class=def> | <pre class="def"> | ||
db.world.find() | |||
db.world.aggregate([{"$match":{}}]) | |||
</pre> | </pre> | ||
</div> | </div> | ||
<div class=q data-lang=" | <div class="q" data-lang="mongo">Returning the first document | ||
<pre class=def> | <pre class="def"> | ||
db.world.findOne() | |||
db.world.find()[0] | |||
db.world.find().limit(1) | |||
db.world.aggregate([{"$limit":1}]) | |||
</pre> | </pre> | ||
</div> | </div> | ||
<div class=q data-lang=" | <div class="q" data-lang="mongo">Returning the '''n'''th document | ||
<pre class=def> | <pre class="def"> | ||
n = 50; | let n = 50; | ||
db.world.find()[n-1] | |||
db.world.find().skip(n-1).limit(1) | |||
db.world.aggregate([{"$skip":n-1},{"$limit":1}]) | |||
</pre> | </pre> | ||
</div> | </div> | ||
<div class=q data-lang=" | <div class="q" data-lang="mongo">Returning the last document | ||
<pre class=def> | <pre class="def"> | ||
db.world.find()[db.world.count()-1] | |||
db.world.find().skip(db.world.count()-1).limit(1) | |||
db.world.aggregate([{"$skip":db.world.count()-1},{"$limit":1}]) | |||
</pre> | </pre> | ||
</div> | </div> | ||
Latest revision as of 00:13, 9 April 2018
Return all documents
db.world.find()
db.world.aggregate([{"$match":{}}])
Returning the first document
db.world.findOne()
db.world.find()[0]
db.world.find().limit(1)
db.world.aggregate([{"$limit":1}])
Returning the nth document
let n = 50;
db.world.find()[n-1]
db.world.find().skip(n-1).limit(1)
db.world.aggregate([{"$skip":n-1},{"$limit":1}])
Returning the last document
db.world.find()[db.world.count()-1]
db.world.find().skip(db.world.count()-1).limit(1)
db.world.aggregate([{"$skip":db.world.count()-1},{"$limit":1}])