Sum and Count - Revision history

40166222 at 16:41, 18 July 2018

2018-07-18T16:41:57Z

← Older revision		Revision as of 16:41, 18 July 2018
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	emit(this.continent, this.population);		emit(this.continent, this.population);
	},		},
	function (k, v) {		function (k, v) {
	return Array.sum(v);		return Array.sum(v);
	},		},

40166222 at 16:41, 18 July 2018

2018-07-18T16:41:26Z

← Older revision		Revision as of 16:41, 18 July 2018
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	</div>		</div>
	<div class="q nonum" data-lang="mongo"><code>.count()</code>		<div class="q nonum" data-lang="mongo"><code>.count()</code>
	<pre class="def"><nowiki>db.world.count({"continent": "Africa"})</nowiki></pre>		<pre class="def"><nowiki>db.world.count({"continent": "Africa"});</nowiki></pre>
	</div>		</div>

40166222 at 16:41, 18 July 2018

2018-07-18T16:41:08Z

← Older revision		Revision as of 16:41, 18 July 2018
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	out: {inline: 1}		out: {inline: 1}
	}		}
	)		);
	</nowiki></pre>		</nowiki></pre>
	</div>		</div>

40166222 at 16:40, 18 July 2018

2018-07-18T16:40:55Z

← Older revision		Revision as of 16:40, 18 July 2018
Line 7:		Line 7:
	</div>		</div>
	<div class="q nonum" data-lang="mongo"><code>.count()</code>		<div class="q nonum" data-lang="mongo"><code>.count()</code>
	<pre class="def">db.world.count({"continent":"Africa"})</pre>		<pre class="def"><nowiki>db.world.count({"continent": "Africa"})</nowiki></pre>
	</div>		</div>

	<div class="q nonum" data-lang="mongo"><code>$sum</code>		<div class="q nonum" data-lang="mongo"><code>$sum</code>
	<pre class="def">		<pre class="def"><nowiki>
	db.world.aggregate([		db.world.aggregate([
	{"$group":{		{"$group": {
	"_id": "$continent",		"_id": "$continent",
	"sum of populations": {$sum: "$population"},		"sum of populations": {$sum: "$population"},
	"count of countries": {$sum: 1}		"count of countries": {$sum: 1}
	}}		}}
	])		]);</nowiki></pre>
	</pre>
	</div>		</div>

	<div class="q nonum" data-lang="mongo"><code>Array.sum()</code>		<div class="q nonum" data-lang="mongo"><code>Array.sum()</code>
	<pre class="def">		<pre class="def"><nowiki>
	db.world.mapReduce(		db.world.mapReduce(
	function(){		function () {
	emit(this.continent, this.population);		emit(this.continent, this.population);
	},		},
	function(k,v){		function (k, v) {
	return Array.sum(v);		return Array.sum(v);
	},		},
	{		{
	out:{inline:1}		out: {inline: 1}
	}		}
	)		)
	</pre>		</nowiki></pre>
	</div>		</div>

40166222 at 02:36, 6 April 2018

2018-04-06T02:36:22Z

← Older revision		Revision as of 02:36, 6 April 2018
Line 19:		Line 19:
	}}		}}
	])		])
	</pre >		</pre>
	</div>		</div>

40166222 at 02:35, 6 April 2018

2018-04-06T02:35:50Z

← Older revision		Revision as of 02:35, 6 April 2018
Line 7:		Line 7:
	</div>		</div>
	<div class="q nonum" data-lang="mongo"><code>.count()</code>		<div class="q nonum" data-lang="mongo"><code>.count()</code>
	<~~div~~ class="def">db.world.count({"continent":"Africa"})</~~div~~>		<pre class="def">db.world.count({"continent":"Africa"})</pre>
	</div>		</div>

	<div class="q nonum" data-lang="mongo"><code>$sum</code>		<div class="q nonum" data-lang="mongo"><code>$sum</code>
	<~~div~~ class="def">		<pre class="def">
	db.world.aggregate([		db.world.aggregate([
	{"$group":{		{"$group":{
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	}}		}}
	])		])
	</~~div~~>		</pre >
	</div>		</div>

	<div class="q nonum" data-lang="mongo"><code>Array.sum()</code>		<div class="q nonum" data-lang="mongo"><code>Array.sum()</code>
	<~~div~~ class="def">		<pre class="def">
	db.world.mapReduce(		db.world.mapReduce(
	function(){		function(){
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	}		}
	)		)
	</~~div~~>		</pre>
	</div>		</div>

40166222 at 02:35, 6 April 2018

2018-04-06T02:35:10Z

← Older revision		Revision as of 02:35, 6 April 2018
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	<code>count()</code> is a cursor method that takes a query and returns a number equal to the amount of documents that matched the query.<br/>		<code>count()</code> is a cursor method that takes a query and returns a number equal to the amount of documents that matched the query.<br/>
	<code>$sum</code> is an aggregation operator availible in the <code>$group</code> stage, that can be used to both sum values and count the number of documents.<br/>		<code>$sum</code> is an aggregation operator availible in the <code>$group</code> stage, that can be used to both sum values and count the number of documents.<br/>
	mapReduce can produce a sum or a count during the results stage by using JavaScript.		<code>mapReduce</code> can produce a sum or a count during the results stage by using JavaScript.
	~~</div>~~
	~~<div class="q nonum" data-lang="mongo">.count()~~
	~~<div class="def">db.world.count({"continent":"Africa"})~~
	</div>		</div>
			<div class="q nonum" data-lang="mongo"><code>.count()</code>
			<div class="def">db.world.count({"continent":"Africa"})</div>
	</div>		</div>

	<div class="q nonum" data-lang="mongo">$sum		<div class="q nonum" data-lang="mongo"><code>$sum</code>
	<div class="def">		<div class="def">
	db.world.aggregate([		db.world.aggregate([
	{"$group":{		{"$group":{
	"_id":"$continent",		"_id": "$continent",
	"sum of populations":{$sum:"$population"},		"sum of populations": {$sum: "$population"},
	"count of countries":{$sum:1}		"count of countries": {$sum: 1}
	}}		}}
	])		])
	</div>		</div>
	</div>		</div>

	<div class="q nonum" data-lang="mongo">Array.sum()		<div class="q nonum" data-lang="mongo"><code>Array.sum()</code>
	<div class="def">		<div class="def">
	db.world.mapReduce(		db.world.mapReduce(
	function(){emit(this.continent, this.population)},		function(){
	function(k,v){ return Array.sum(v) },		emit(this.continent, this.population);
	{out:{inline:1}}		},
			function(k,v){
			return Array.sum(v);
			},
			{
			out:{inline:1}
			}
	)		)
	</div>		</div>
	</div>		</div>

Andr3w at 15:33, 3 December 2015

2015-12-03T15:33:57Z

← Older revision		Revision as of 15:33, 3 December 2015
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	{out:{inline:1}}		{out:{inline:1}}
	)		)

	~~pp.pprint(temp['results'])~~
	</div>		</div>
	</div>		</div>

Andr3w at 15:33, 3 December 2015

2015-12-03T15:33:00Z

← Older revision		Revision as of 15:33, 3 December 2015
Line 1:		Line 1:
	~~<pre class=setup>~~
	~~#ENCODING~~
	~~import io~~
	~~import sys~~
	~~sys.stdout = io.TextIOWrapper(sys.stdout.buffer, encoding='utf-16')~~
	~~#MONGO~~
	~~from pymongo import MongoClient~~
	~~client = MongoClient()~~
	~~client.progzoo.authenticate('scott','tiger')~~
	~~db = client['progzoo']~~
	~~#PRETTY~~
	~~import pprint~~
	~~pp = pprint.PrettyPrinter(indent=4)~~
	~~#CODE~~
	~~from bson.code import Code~~
	~~</pre>~~
	{{TopTenTips}}		{{TopTenTips}}
	<div style="min-height:25em">		<div style="min-height:25em">
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	mapReduce can produce a sum or a count during the results stage by using JavaScript.		mapReduce can produce a sum or a count during the results stage by using JavaScript.
	</div>		</div>
	<div class="q nonum" data-lang="~~py3~~">.count()		<div class="q nonum" data-lang="mongo">.count()
	<div class="def">~~print(~~db.world.count({"continent":"Africa"}))		<div class="def">db.world.count({"continent":"Africa"})
	</div>		</div>
	</div>		</div>

	<div class="q nonum" data-lang="~~py3~~">$sum		<div class="q nonum" data-lang="mongo">$sum
	<div class="def">~~pp.pprint(list(~~		<div class="def">
	db.world.aggregate([		db.world.aggregate([
	{"$group":{		{"$group":{
	"_id":"$continent",		"_id":"$continent",
	"sum of populations":{"$sum":"$population"},		"sum of populations":{$sum:"$population"},
	"count of countries":{"$sum":1}		"count of countries":{$sum:1}
	}}		}}
	])		])
	))
	</div>		</div>
	</div>		</div>

	<div class="q nonum" data-lang="~~py3~~">Array.sum()		<div class="q nonum" data-lang="mongo">Array.sum()
	<div class="def">~~temp =~~ db.world.~~map_reduce~~(		<div class="def">
	~~map=Code("~~function(){emit(this.continent, this.population)}"),		db.world.mapReduce(
	~~reduce=Code("""~~function(k,v){		function(){emit(this.continent, this.population)},
	return Array.sum(v)		function(k,v){ return Array.sum(v) },
	}		{out:{inline:1}}
	~~""")~~,
	out={"inline":1}
	)		)

40166222 at 13:29, 28 July 2015

2015-07-28T13:29:36Z

← Older revision		Revision as of 13:29, 28 July 2015
Line 22:		Line 22:
	mapReduce can produce a sum or a count during the results stage by using JavaScript.		mapReduce can produce a sum or a count during the results stage by using JavaScript.
	</div>		</div>
	<div class=q data-lang="py3">.count()		<div class="q nonum" data-lang="py3">.count()
	<div class="def">print(db.world.count({"continent":"Africa"}))		<div class="def">print(db.world.count({"continent":"Africa"}))
	</div>		</div>
	</div>		</div>

	<div class=q data-lang="py3">$sum		<div class="q nonum" data-lang="py3">$sum
	<div class="def">pp.pprint(list(		<div class="def">pp.pprint(list(
	db.world.aggregate([		db.world.aggregate([
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	</div>		</div>

	<div class=q data-lang="py3">Array.sum()		<div class="q nonum" data-lang="py3">Array.sum()
	<div class="def">temp = db.world.map_reduce(		<div class="def">temp = db.world.map_reduce(
	map=Code("function(){emit(this.continent, this.population)}"),		map=Code("function(){emit(this.continent, this.population)}"),