Space Race/MATCH Tutorial - Revision history

ChrisHouston at 08:53, 9 December 2019

2019-12-09T08:53:42Z

← Older revision		Revision as of 08:53, 9 December 2019
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	==Cypher Cheat Sheet==		==Cypher Cheat Sheet==
	[[Space_Race/Cypher_Cheat_Sheet]]		[[Space_Race/Cypher_Cheat_Sheet]]
			==Database Schema==
			[[Space_Race/Schema]]

	==Institutions==		==Institutions==

ChrisHouston at 08:49, 9 December 2019

2019-12-09T08:49:48Z

← Older revision		Revision as of 08:49, 9 December 2019
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	==Cypher Cheat Sheet==		==Cypher Cheat Sheet==
	[/Space_Race/Cypher_Cheat_Sheet]		[[Space_Race/Cypher_Cheat_Sheet]]

	==Institutions==		==Institutions==

ChrisHouston at 08:48, 9 December 2019

2019-12-09T08:48:41Z

← Older revision		Revision as of 08:48, 9 December 2019
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	==Cypher Cheat Sheet==		==Cypher Cheat Sheet==
	[Space_Race/Cypher_Cheat_Sheet]		[/Space_Race/Cypher_Cheat_Sheet]

	==Institutions==		==Institutions==

ChrisHouston at 08:48, 9 December 2019

2019-12-09T08:48:18Z

← Older revision		Revision as of 08:48, 9 December 2019
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	[http://nosqlzoo.net/mw/visproject/visualisation.php Click here for 3d graph visualisation]		[http://nosqlzoo.net/mw/visproject/visualisation.php Click here for 3d graph visualisation]

			==Cypher Cheat Sheet==
			[Space_Race/Cypher_Cheat_Sheet]

	==Institutions==		==Institutions==

ChrisHouston at 08:45, 9 December 2019

2019-12-09T08:45:05Z

← Older revision		Revision as of 08:45, 9 December 2019
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	<pre class="def"><nowiki>MATCH(n:Astronaut) RETURN n AS Astronauts;</nowiki>		<pre class="def"><nowiki>MATCH(n:Astronaut) RETURN n AS Astronauts;</nowiki>
	</pre>		</pre>
	<pre class="ans"><nowiki>MATCH(n:Institution) RETURN n AS ~~Insitutions~~; </nowiki>		<pre class="ans"><nowiki>MATCH(n:Institution) RETURN n AS Institutions; </nowiki>
	</pre>		</pre>
	</div>		</div>

ChrisHouston at 12:42, 1 December 2019

2019-12-01T12:42:44Z

← Older revision		Revision as of 12:42, 1 December 2019
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	<pre class="def"><nowiki>MATCH(m:LaunchVehicle)RETURN m.name, toInteger(m.launches); </nowiki>		<pre class="def"><nowiki>MATCH(m:LaunchVehicle)RETURN m.name, toInteger(m.launches); </nowiki>
	</pre>		</pre>
	<pre class="ans"><nowiki>MATCH(m:LaunchVehicle) RETURN m.name AS Name, ((toFloat(m.failures)/toFloat(m.launches))*100) AS PercentageFailureRate ORDER BY PercentageFailureRate;</nowiki>		<pre class="ans"><nowiki>MATCH(m:LaunchVehicle) RETURN m.name AS Name, ((toFloat(m.failures)/toFloat(m.launches))*100) AS PercentageFailureRate ORDER BY PercentageFailureRate DESC;</nowiki>
	</pre>		</pre>
	</div>		</div>

	{{Acknowledgements}}		{{Acknowledgements}}

ChrisHouston at 12:42, 1 December 2019

2019-12-01T12:42:25Z

← Older revision		Revision as of 12:42, 1 December 2019
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	<pre class="def"><nowiki>MATCH(m:LaunchVehicle)RETURN m.name, toInteger(m.launches); </nowiki>		<pre class="def"><nowiki>MATCH(m:LaunchVehicle)RETURN m.name, toInteger(m.launches); </nowiki>
	</pre>		</pre>
	<pre class="ans"><nowiki>MATCH(m:LaunchVehicle) RETURN m.name AS Name, ~~toString(~~((toFloat(m.failures)/toFloat(m.launches))*100)~~)+'%'~~ AS PercentageFailureRate ORDER BY PercentageFailureRate;</nowiki>		<pre class="ans"><nowiki>MATCH(m:LaunchVehicle) RETURN m.name AS Name, ((toFloat(m.failures)/toFloat(m.launches))*100) AS PercentageFailureRate ORDER BY PercentageFailureRate;</nowiki>
	</pre>		</pre>
	</div>		</div>

	{{Acknowledgements}}		{{Acknowledgements}}

ChrisHouston at 12:41, 1 December 2019

2019-12-01T12:41:57Z

← Older revision		Revision as of 12:41, 1 December 2019
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	<pre class="def"><nowiki>MATCH(m:LaunchVehicle)RETURN m.name, toInteger(m.launches); </nowiki>		<pre class="def"><nowiki>MATCH(m:LaunchVehicle)RETURN m.name, toInteger(m.launches); </nowiki>
	</pre>		</pre>
	<pre class="ans"><nowiki>MATCH(m:LaunchVehicle) RETURN m.name AS Name, toString(((toFloat(m.failures)/toFloat(m.launches))*100))+'%' AS PercentageFailureRate;</nowiki>		<pre class="ans"><nowiki>MATCH(m:LaunchVehicle) RETURN m.name AS Name, toString(((toFloat(m.failures)/toFloat(m.launches))*100))+'%' AS PercentageFailureRate ORDER BY PercentageFailureRate;</nowiki>
	</pre>		</pre>
	</div>		</div>

	{{Acknowledgements}}		{{Acknowledgements}}

ChrisHouston at 12:40, 1 December 2019

2019-12-01T12:40:56Z

← Older revision		Revision as of 12:40, 1 December 2019
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	<div class="q nonum" data-lang="neo4j">		<div class="q nonum" data-lang="neo4j">
	<p>Use <code>MATCH</code> and <code>RETURN</code> to return nodes. Use <code>:</code> to specify what label(s) you wish the returned nodes to have. Not specifying any label will return ALL nodes</p>		<p>Use <code>MATCH</code> and <code>RETURN</code> to return nodes. Use <code>:</code> to specify what label(s) you wish the returned nodes to have. Not specifying any label will return ALL nodes</p>
			<p>Using AS can alias the result column to whatever you wish, as long as it does not have spaces</p>
	<p class='strong'>Show Institutions instead of Astronauts</p>		<p class='strong'>Show Institutions instead of Astronauts</p>
	<pre class="def"><nowiki>MATCH(n:Astronaut) RETURN n;</nowiki>		<pre class="def"><nowiki>MATCH(n:Astronaut) RETURN n AS Astronauts;</nowiki>
	</pre>		</pre>
	<pre class="ans"><nowiki>MATCH(n:Institution) RETURN n; </nowiki>		<pre class="ans"><nowiki>MATCH(n:Institution) RETURN n AS Insitutions; </nowiki>
	</pre>		</pre>
	</div>		</div>
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	<p>When simply matching based on properties of a node, use the <code>{}</code> with the format <code>{property:value}</code>		<p>When simply matching based on properties of a node, use the <code>{}</code> with the format <code>{property:value}</code>
	<p class='strong'>Return Neil Armstrong's date of birth</p>		<p class='strong'>Return Neil Armstrong's date of birth</p>
	<pre class="def"><nowiki>MATCH(n:Astronaut{surname:"Gagarin",first_name:"Yuri"})RETURN n.dob;</nowiki>		<pre class="def"><nowiki>MATCH(n:Astronaut{surname:"Gagarin",first_name:"Yuri"})RETURN n.dob AS DateOfBirth;</nowiki>
	</pre>		</pre>
	<pre class="ans"><nowiki>MATCH(n:Astronaut{surname:"Armstrong",first_name:"Neil"})RETURN n.dob;</nowiki>		<pre class="ans"><nowiki>MATCH(n:Astronaut{surname:"Armstrong",first_name:"Neil"})RETURN n.dob AS DateOfBirth;</nowiki>
	</pre>		</pre>
	</div>		</div>
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	<p><code>ORDER BY</code> works similarly to SQL, defaulting to ordering from low to high value. Adding <code>DESC</code> instead orders the result in descending order</p>		<p><code>ORDER BY</code> works similarly to SQL, defaulting to ordering from low to high value. Adding <code>DESC</code> instead orders the result in descending order</p>
	<p class='strong'>Return the names of the Astronauts ordered by their date of birth, from oldest to youngest.</p>		<p class='strong'>Return the names of the Astronauts ordered by their date of birth, from oldest to youngest.</p>
	<pre class="def"><nowiki>MATCH(n:Astronaut) RETURN n.first_name, n.surname ORDER BY n.surname;</nowiki>		<pre class="def"><nowiki>MATCH(n:Astronaut) RETURN n.first_name AS FirstName, n.surname AS Surname ORDER BY n.surname;</nowiki>
	</pre>		</pre>
	<pre class="ans"><nowiki>MATCH(n:Astronaut) RETURN n.first_name, n.surname ORDER BY n.dob;</nowiki>		<pre class="ans"><nowiki>MATCH(n:Astronaut) RETURN n.first_name AS FirstName, n.surname As Surname ORDER BY n.dob;</nowiki>
	</pre>		</pre>
	</div>		</div>
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	<p> This can be checked using the <code>EXISTS()</code> function</p>		<p> This can be checked using the <code>EXISTS()</code> function</p>
	<p class='strong'>Return the nicknames of the Astronauts who have them in reverse alphabetical order</p>		<p class='strong'>Return the nicknames of the Astronauts who have them in reverse alphabetical order</p>
	<pre class="def"><nowiki>MATCH(n:Astronaut)WHERE EXISTS(n.middle_names) RETURN n.middle_names; </nowiki>		<pre class="def"><nowiki>MATCH(n:Astronaut)WHERE EXISTS(n.middle_names) RETURN n.middle_names AS MiddleNames; </nowiki>
	</pre>		</pre>
	<pre class="ans"><nowiki>MATCH(n:Astronaut)WHERE EXISTS(n.nickname) RETURN n.nickname ORDER BY n.nickname DESC;</nowiki>		<pre class="ans"><nowiki>MATCH(n:Astronaut)WHERE EXISTS(n.nickname) RETURN n.nickname AS Nicknames ORDER BY n.nickname DESC;</nowiki>
			</pre>
			</div>

			==Counting up the missions==
			<div class="q nonum" data-lang="neo4j">
			<p>As in SQL, aggregate functions can be applied to the results of the MATCH query. Unlike SQL you do not need to group by other non-aggregate parameters </p>
			<p>Functions include <code>count()</code>, <code>avg()</code>, <code>min()</code>, <code>max()</code> and many more</p>
			<p class='strong'>Return the number of missions that took place in the Space Race.</p>
			<pre class="def"><nowiki>MATCH(m:LaunchVehicle)RETURN count(m) AS Count; </nowiki>
			</pre>
			<pre class="ans"><nowiki>MATCH(m:Mission) RETURN count(m) AS Count;</nowiki>
	</pre>		</pre>
	</div>		</div>

	==Failure Rate==		==Failure Rate==
	<div>		<div class="q nonum" data-lang="neo4j">
			<p>Arithmetic and string operations can also be used in the return statement. Strings can be parsed in to integers or floats using the <code>toInteger()</code> or <code>toFloat()</code> functions</p>
			<p>The reverse can be done using the <code>toString()</code> function.
			<p class='strong'>Return the name and percentage failure rate for each LaunchVehicle, ordered by number of failures in descending order.</p>
			<pre class="def"><nowiki>MATCH(m:LaunchVehicle)RETURN m.name, toInteger(m.launches); </nowiki>
			</pre>
			<pre class="ans"><nowiki>MATCH(m:LaunchVehicle) RETURN m.name AS Name, toString(((toFloat(m.failures)/toFloat(m.launches))*100))+'%' AS PercentageFailureRate;</nowiki>
			</pre>
			</div>

	{{Acknowledgements}}		{{Acknowledgements}}

ChrisHouston at 12:04, 1 December 2019

2019-12-01T12:04:38Z

← Older revision		Revision as of 12:04, 1 December 2019
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	<div class="q nonum" data-lang="neo4j">		<div class="q nonum" data-lang="neo4j">
	<p><code>ORDER BY</code> works similarly to SQL, defaulting to ordering from low to high value. Adding <code>DESC</code> instead orders the result in descending order</p>		<p><code>ORDER BY</code> works similarly to SQL, defaulting to ordering from low to high value. Adding <code>DESC</code> instead orders the result in descending order</p>
	<p class='strong'>Return the names of the Astronauts ordered by their date of birth from ~~earlier~~ to ~~later~~</p>		<p class='strong'>Return the names of the Astronauts ordered by their date of birth, from oldest to youngest.</p>
	<pre class="def"><nowiki>MATCH(n:Astronaut) RETURN n.first_name, n.surname ORDER BY n.surname;</nowiki>		<pre class="def"><nowiki>MATCH(n:Astronaut) RETURN n.first_name, n.surname ORDER BY n.surname;</nowiki>
	</pre>		</pre>
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	</pre>		</pre>
	</div>		</div>

			==Failure Rate==
			<div>

	{{Acknowledgements}}		{{Acknowledgements}}