Graph database presentation to Nashville PHP in November, 2014.

1. Leveraging the Power of
Graph Databases
in PHP
Jeremy Kendall
Nashville PHP
November 2014

2. Obligatory Intro Slide

3. Also - New Father

4. What Kind of
Database?

5. Graphs != Charts
https://www.flickr.com/photos/markgroves/3065192499/

6. Graphs != Charts
http://stephenwildish.tumblr.com/post/101408321763/friday-project-witch-moral-compass

7. Graph Databases

8. Graph Databases
• Data Model!
• Nodes with properties
• Typed relationships

9. Graph Databases
• Data Model!
• Nodes with properties
• Typed relationships
• Strengths!
• Highly connected data
• ACID

10. Graph Databases
• Data Model!
• Nodes with properties
• Typed relationships
• Strengths!
• Highly connected data
• ACID
• Weaknesses!
• Paradigm shift

11. Graph Databases
• Data Model!
• Nodes with properties
• Typed relationships
• Strengths!
• Highly connected data
• ACID
• Weaknesses!
• Paradigm shift
• Examples!
• Neo4j, Titan, OrientDB

12. Why Care?

13. Why Care?
• All the NoSQL Joy
• Schema-less
• Semi-structured data

14. Why Care?
• All the NoSQL Joy
• Schema-less
• Semi-structured data
• Escape from JOIN Hell

15. Why Care?
• All the NoSQL Joy
• Schema-less
• Semi-structured data
• Escape from JOIN Hell
• Speed

16. Why Care?

17. Why Care?
• Relationships have 1st class status

18. Why Care?
• Relationships have 1st class status
• Just as important as the objects connecting them

19. Why Care?
• Relationships have 1st class status
• Just as important as the objects connecting them
• You can have properties & labels

20. Why Care?
• Relationships have 1st class status
• Just as important as the objects connecting them
• You can have properties & labels
• Multiple relationships

21. Why Care?

22. Speed
Depth MySQL Query Time Neo4j Query Time Records Returned
2 0.028 (28 MS) 0.04 ~900
3 0.213 0.06 ~999
4 10.273 0.07 ~999
5 92.613 0.07 ~999
1,000 people with an average 50 friends each

23. Crazy Speed
Depth MySQL Query Time Neo4j Query Time Records Returned
2 0.016 (16 MS) 0.01 ~2500
3 30.27 0.168 ~125,000
4 1543.505 1.359 ~600,000
5 Stopped after 1 hour 2.132 ~800,000
1,000,000 people with an average 50 friends each

24. Neo4j + Cypher

25. Cypher
• Neo4j’s declarative query language
• Easy to pick up
• Some clauses and concepts familiar from SQL

26. Simple Example

27. Goal

28. Create Some Nodes
CREATE (jk:Person { name: "Jeremy Kendall" })!
CREATE (gs:Company { name: "Graph Story" })!
!
CREATE (tn:State { name: "Tennessee" })!
CREATE (memphis:City { name: "Memphis" })!
CREATE (nashville:City { name: "Nashville" })!
!
CREATE (hotchicken:Food { name: "Hot Chicken" })!
CREATE (bbq:Food { name: "Barbecue" })!
CREATE (photography:Hobby { name: "Photography" })!
CREATE (language:Language { name: "PHP" })!
!
// . . . snip . . .!

29. Create Some Relationships
// . . . snip . . .!
!
CREATE (jk)-[:WORKS_AT { title: {"CTO"}]->(gs),!
(jk)-[:LIVES_IN]->(memphis)-[:LIVED_IN]->(nashville),!
(hotchicken)-[:ONLY_IN]->(nashville),!
(bbq)-[:ONLY_IN]->(memphis),!
(jk)-[:LOVES]->(hotchicken),!
!
// . . . snip . . .!

30. Create Some Relationships
// . . . snip . . .!
!
CREATE (jk)-[:WORKS_AT { title: {"CTO"}]->(gs),!
(jk)-[:LIVES_IN]->(memphis)-[:LIVED_IN]->(nashville),!
(hotchicken)-[:ONLY_IN]->(nashville),!
(bbq)-[:ONLY_IN]->(memphis),!
(jk)-[:LOVES]->(hotchicken),!
!
// . . . snip . . .!

31. Create Some Relationships
// . . . snip . . .!
!
CREATE (jk)-[:WORKS_AT { title: {"CTO"}]->(gs),!
(jk)-[:LIVES_IN]->(memphis)-[:LIVED_IN]->(nashville),!
(hotchicken)-[:ONLY_IN]->(nashville),!
(bbq)-[:ONLY_IN]->(memphis),!
(jk)-[:LOVES]->(hotchicken),!
!
// . . . snip . . .!

32. Create Some Relationships
// . . . snip . . .!
!
CREATE (jk)-[:WORKS_AT { title: {"CTO"}]->(gs),!
(jk)-[:LIVES_IN]->(memphis)-[:LIVED_IN]->(nashville),!
(hotchicken)-[:ONLY_IN]->(nashville),!
(bbq)-[:ONLY_IN]->(memphis),!
(jk)-[:LOVES]->(hotchicken),!
!
// . . . snip . . .!

33. Example Cypher Query
MATCH (p:Person { name: "Jeremy Kendall" })-[:LOVES]->(l)!
WITH p, l!
MATCH (p)-[:WORKS_AT]->(j)!
WITH p, l, j!
MATCH (p)-[:LIVES_IN]->(c:City)-[:LIVED_IN*0..]->(o:City)!
RETURN p, l, j, o

34. Example Cypher Query
MATCH (p:Person { name: "Jeremy Kendall" })-[:LOVES]->(l)!
WITH p, l!
MATCH (p)-[:WORKS_AT]->(j)!
WITH p, l, j!
MATCH (p)-[:LIVES_IN]->(c:City)-[:LIVED_IN*0..]->(o:City)!
RETURN p, l, j, o

35. Example Cypher Query
MATCH (p:Person { name: "Jeremy Kendall" })-[:LOVES]->(l)!
WITH p, l!
MATCH (p)-[:WORKS_AT]->(j)!
WITH p, l, j!
MATCH (p)-[:LIVES_IN]->(c:City)-[:LIVED_IN*0..]->(o:City)!
RETURN p, l, j, o

36. Example Cypher Query
MATCH (p:Person { name: "Jeremy Kendall" })-[:LOVES]->(l)!
WITH p, l!
MATCH (p)-[:WORKS_AT]->(j)!
WITH p, l, j!
MATCH (p)-[:LIVES_IN]->(c:City)-[:LIVED_IN*0..]->(o:City)!
RETURN p, l, j, o

37. Example Cypher Query
MATCH (p:Person { name: "Jeremy Kendall" })-[:LOVES]->(l)!
WITH p, l!
MATCH (p)-[:WORKS_AT]->(j)!
WITH p, l, j!
MATCH (p)-[:LIVES_IN]->(c:City)-[:LIVED_IN*0..]->(o:City)!
RETURN p, l, j, o

38. Example Cypher Query
MATCH (p:Person { name: "Jeremy Kendall" })-[:LOVES]->(l)!
WITH p, l!
MATCH (p)-[:WORKS_AT]->(j)!
WITH p, l, j!
MATCH (p)-[:LIVES_IN]->(c:City)-[:LIVED_IN*0..]->(o:City)!
RETURN p, l, j, o

39. Example Cypher Query
MATCH (p:Person { name: "Jeremy Kendall" })-[:LOVES]->(l)!
WITH p, l!
MATCH (p)-[:WORKS_AT]->(j)!
WITH p, l, j!
MATCH (p)-[:LIVES_IN]->(c:City)-[:LIVED_IN*0..]->(o:City)!
RETURN p, l, j, o

40. Query Result

41. Neo4j + PHP

42. Neo4jPHP
• PHP wrapper for the Neo4j REST API
• Installable via Composer
• Used internally at Graph Story
• Used in this presentation
• Well tested
• https://packagist.org/packages/everyman/
neo4jphp

43. Also see: NeoClient
• Written by Neoxygen
• Alternative PHP wrapper for the Neo4j REST API
• Installable via Composer
• Under review for internal use at Graph Story
• Well tested
• https://packagist.org/packages/neoxygen/neoclient

44. Connecting
$neo4jClient = new EverymanNeo4jClient(!
‘yourgraph.example.com’, !
7473!
);!
!
$neo4jClient->getTransport()!
->setAuth('username', 'password')!
->getTransport()->useHttps();

45. Creating a Node and Label
$node = new Node($neo4jClient);!
!
$label = $neo4jClient->makeLabel('Person');!
!
$node->setProperty('name', ‘Jeremy Kendall');!
!
$node->save()->addLabels(array($label));

46. Searching
// Searching for a label by property!
$label = $neo4jClient->makeLabel('Person');!
$nodes = $label->getNodes('name', $name);

47. Querying (Cypher)
$queryString = !
'MATCH (p:Person { name: { name }}) RETURN p';!
!
$query = new EverymanNeo4jCypherQuery(!
$neo4jClient,!
$queryString,!
['name' => ‘Jeremy Kendall']!
);!
!
$result = $query->getResultSet();

48. Named Parameters

49. Named Parameters
$queryString = !
'MATCH (p:Person { name: { name }}) RETURN p';!
!
$query = new EverymanNeo4jCypherQuery(!
$neo4jClient,!
$queryString,!
['name' => ‘Jeremy Kendall']!
);!
!
$result = $query->getResultSet();

50. Named Parameters
$queryString = !
'MATCH (p:Person { name: { name }}) RETURN p';!
!
$query = new EverymanNeo4jCypherQuery(!
$neo4jClient,!
$queryString,!
['name' => ‘Jeremy Kendall']!
);!
!
$result = $query->getResultSet();

51. Content Modeling:
News Feeds

52. News Feed
• Modeled as a list of posts
• Newest post first
• All subsequent posts follow
• Relationships: LASTPOST and NEXTPOST

53. LASTPOST

54. NEXTPOST

55. The Content Model
class Content!
{!
public $node;!
public $nodeId;!
public $contentId;!
public $title;!
public $url;!
public $tagstr;!
public $timestamp;!
public $userNameForPost;!
public $owner = false;!
}

56. Adding Content
public static function add($username, Content $content)!
{!
$queryString =<<<CYPHER!
MATCH (user { username: {u}})!
OPTIONAL MATCH (user)-[r:LASTPOST]->(lastpost)!
DELETE r!
CREATE (user)-[:LASTPOST]->(p:Content { title:{title}, url:{url}, tagstr:{tagstr}, timestamp:{timestamp}, contentId:
{contentId} })!
WITH p, collect(lastpost) as lastposts!
FOREACH (x IN lastposts | CREATE p-[:NEXTPOST]->x)!
RETURN p, {u} as username, true as owner!
CYPHER;!
!
$query = new Query(!
Neo4jClient::client(),!
$queryString,!
array(!
'u' => $username,!
'title' => $content->title,!
'url' => $content->url,!
'tagstr' => $content->tagstr,!
'timestamp' => time(),!
'contentId' => uniqid()!
)!
);!
$result = $query->getResultSet();!
!
return self::returnMappedContent($result);!
}

57. Adding Content
public static function add($username, Content $content)!
{!
$queryString =<<<CYPHER!
MATCH (user { username: {u}})!
OPTIONAL MATCH (user)-[r:LASTPOST]->(lastpost)!
DELETE r!
CREATE (user)-[:LASTPOST]->(p:Content { title:{title}, url:{url}, tagstr:{tagstr}, timestamp:{timestamp}, contentId:
{contentId} })!
WITH p, collect(lastpost) as lastposts!
FOREACH (x IN lastposts | CREATE p-[:NEXTPOST]->x)!
RETURN p, {u} as username, true as owner!
CYPHER;!
!
$query = new Query(!
Neo4jClient::client(),!
$queryString,!
array(!
'u' => $username,!
'title' => $content->title,!
'url' => $content->url,!
'tagstr' => $content->tagstr,!
'timestamp' => time(),!
'contentId' => uniqid()!
)!
);!
$result = $query->getResultSet();!
!
return self::returnMappedContent($result);!
}

58. Adding Content
public static function add($username, Content $content)!
{!
$queryString =<<<CYPHER!
MATCH (user { username: {u}})!
OPTIONAL MATCH (user)-[r:LASTPOST]->(lastpost)!
DELETE r!
CREATE (user)-[:LASTPOST]->(p:Content { title:{title}, url:{url}, tagstr:{tagstr}, timestamp:{timestamp}, contentId:
{contentId} })!
WITH p, collect(lastpost) as lastposts!
FOREACH (x IN lastposts | CREATE p-[:NEXTPOST]->x)!
RETURN p, {u} as username, true as owner!
CYPHER;!
!
$query = new Query(!
Neo4jClient::client(),!
$queryString,!
array(!
'u' => $username,!
'title' => $content->title,!
'url' => $content->url,!
'tagstr' => $content->tagstr,!
'timestamp' => time(),!
'contentId' => uniqid()!
)!
);!
$result = $query->getResultSet();!
!
return self::returnMappedContent($result);!
}

59. Adding Content
MATCH (user { username: {u}})!
OPTIONAL MATCH (user)-[r:LASTPOST]->(lastpost)!
DELETE r!
CREATE (user)-[:LASTPOST]->(p:Content { title:{title}, url:
{url}, tagstr:{tagstr}, timestamp:{timestamp}, contentId:
{contentId} })!
WITH p, collect(lastpost) as lastposts!
FOREACH (x IN lastposts | CREATE p-[:NEXTPOST]->x)!
RETURN p, {u} as username, true as owner

60. Adding Content
MATCH (user { username: {u}})!
OPTIONAL MATCH (user)-[r:LASTPOST]->(lastpost)!
DELETE r!
CREATE (user)-[:LASTPOST]->(p:Content { title:{title}, url:
{url}, tagstr:{tagstr}, timestamp:{timestamp}, contentId:
{contentId} })!
WITH p, collect(lastpost) as lastposts!
FOREACH (x IN lastposts | CREATE p-[:NEXTPOST]->x)!
RETURN p, {u} as username, true as owner

61. Adding Content
MATCH (user { username: {u}})!
OPTIONAL MATCH (user)-[r:LASTPOST]->(lastpost)!
DELETE r!
CREATE (user)-[:LASTPOST]->(p:Content { title:{title}, url:
{url}, tagstr:{tagstr}, timestamp:{timestamp}, contentId:
{contentId} })!
WITH p, collect(lastpost) as lastposts!
FOREACH (x IN lastposts | CREATE p-[:NEXTPOST]->x)!
RETURN p, {u} as username, true as owner

62. Adding Content
MATCH (user { username: {u}})!
OPTIONAL MATCH (user)-[r:LASTPOST]->(lastpost)!
DELETE r!
CREATE (user)-[:LASTPOST]->(p:Content { title:{title}, url:
{url}, tagstr:{tagstr}, timestamp:{timestamp}, contentId:
{contentId} })!
WITH p, collect(lastpost) as lastposts!
FOREACH (x IN lastposts | CREATE p-[:NEXTPOST]->x)!
RETURN p, {u} as username, true as owner

63. Adding Content
MATCH (user { username: {u}})!
OPTIONAL MATCH (user)-[r:LASTPOST]->(lastpost)!
DELETE r!
CREATE (user)-[:LASTPOST]->(p:Content { title:{title}, url:
{url}, tagstr:{tagstr}, timestamp:{timestamp}, contentId:
{contentId} })!
WITH p, collect(lastpost) as lastposts!
FOREACH (x IN lastposts | CREATE p-[:NEXTPOST]->x)!
RETURN p, {u} as username, true as owner

64. Adding Content
MATCH (user { username: {u}})!
OPTIONAL MATCH (user)-[r:LASTPOST]->(lastpost)!
DELETE r!
CREATE (user)-[:LASTPOST]->(p:Content { title:{title}, url:
{url}, tagstr:{tagstr}, timestamp:{timestamp}, contentId:
{contentId} })!
WITH p, collect(lastpost) as lastposts!
FOREACH (x IN lastposts | CREATE p-[:NEXTPOST]->x)!
RETURN p, {u} as username, true as owner

65. Adding Content
$query = new Query(!
$neo4jClient,!
$queryString,!
array(!
'u' => $username,!
'title' => $content->title,!
'url' => $content->url,!
'tagstr' => $content->tagstr,!
'timestamp' => time(),!
'contentId' => uniqid()!
)!
);!
!
$result = $query->getResultSet();

66. Retrieving Content
public static function getContent($username, $skip)!
{!
$queryString = <<<CYPHER!
MATCH (u:User { username: { u }})-[:FOLLOWS*0..1]->f!
WITH DISTINCT f, u!
MATCH f-[:LASTPOST]-lp-[:NEXTPOST*0..]-p!
RETURN p, f.username as username, f = u as owner!
ORDER BY p.timestamp desc SKIP { skip } LIMIT 4!
CYPHER;!
!
$query = new Query(!
Neo4jClient::client(),!
$queryString,!
array(!
'u' => $username,!
'skip' => $skip,!
)!
);!
!
$result = $query->getResultSet();!
!
return self::returnMappedContent($result);!
}

67. Retrieving Content
MATCH (u:User { username: { u }})-[:FOLLOWS*0..1]->f!
WITH DISTINCT f, u!
MATCH f-[:LASTPOST]-lp-[:NEXTPOST*0..]-p!
RETURN p, f.username as username, f = u as owner!
ORDER BY p.timestamp desc SKIP { skip } LIMIT 4

68. Retrieving Content
MATCH (u:User { username: { u }})-[:FOLLOWS*0..1]->f!
WITH DISTINCT f, u!
MATCH f-[:LASTPOST]-lp-[:NEXTPOST*0..]-p!
RETURN p, f.username as username, f = u as owner!
ORDER BY p.timestamp desc SKIP { skip } LIMIT 4

69. Retrieving Content
MATCH (u:User { username: { u }})-[:FOLLOWS*0..1]->f!
WITH DISTINCT f, u!
MATCH f-[:LASTPOST]-lp-[:NEXTPOST*0..]-p!
RETURN p, f.username as username, f = u as owner!
ORDER BY p.timestamp desc SKIP { skip } LIMIT 4

70. Retrieving Content
MATCH (u:User { username: { u }})-[:FOLLOWS*0..1]->f!
WITH DISTINCT f, u!
MATCH f-[:LASTPOST]-lp-[:NEXTPOST*0..]-p!
RETURN p, f.username as username, f = u as owner!
ORDER BY p.timestamp desc SKIP { skip } LIMIT 4

71. Retrieving Content
MATCH (u:User { username: { u }})-[:FOLLOWS*0..1]->f!
WITH DISTINCT f, u!
MATCH f-[:LASTPOST]-lp-[:NEXTPOST*0..]-p!
RETURN p, f.username as username, f = u as owner!
ORDER BY p.timestamp desc SKIP { skip } LIMIT 4

72. Retrieving Content
MATCH (u:User { username: { u }})-[:FOLLOWS*0..1]->f!
WITH DISTINCT f, u!
MATCH f-[:LASTPOST]-lp-[:NEXTPOST*0..]-p!
RETURN p, f.username as username, f = u as owner!
ORDER BY p.timestamp desc SKIP { skip } LIMIT 4

73. Editing Content
public static function edit(Content $content)!
{!
$updatedAt = time();!
!
$node = $content->node;!
$node->setProperty('title', $content->title);!
$node->setProperty('url', $content->url);!
$node->setProperty('tagstr', $content->tagstr);!
$node->setProperty('updated', $updatedAt);!
$node->save();!
!
$content->updated = $updatedAt;!
!
return $content;!
}

74. Editing Content
public static function edit(Content $content)!
{!
$updatedAt = time();!
!
$node = $content->node;!
$node->setProperty('title', $content->title);!
$node->setProperty('url', $content->url);!
$node->setProperty('tagstr', $content->tagstr);!
$node->setProperty('updated', $updatedAt);!
$node->save();!
!
$content->updated = $updatedAt;!
!
return $content;!
}

75. Editing Content
public static function edit(Content $content)!
{!
$updatedAt = time();!
!
$node = $content->node;!
$node->setProperty('title', $content->title);!
$node->setProperty('url', $content->url);!
$node->setProperty('tagstr', $content->tagstr);!
$node->setProperty('updated', $updatedAt);!
$node->save();!
!
$content->updated = $updatedAt;!
!
return $content;!
}

76. Editing Content
public static function edit(Content $content)!
{!
$updatedAt = time();!
!
$node = $content->node;!
$node->setProperty('title', $content->title);!
$node->setProperty('url', $content->url);!
$node->setProperty('tagstr', $content->tagstr);!
$node->setProperty('updated', $updatedAt);!
$node->save();!
!
$content->updated = $updatedAt;!
!
return $content;!
}

77. Editing Content
public static function edit(Content $content)!
{!
$updatedAt = time();!
!
$node = $content->node;!
$node->setProperty('title', $content->title);!
$node->setProperty('url', $content->url);!
$node->setProperty('tagstr', $content->tagstr);!
$node->setProperty('updated', $updatedAt);!
$node->save();!
!
$content->updated = $updatedAt;!
!
return $content;!
}

78. Deleting Content
public static function delete($username, $contentId)!
{!
$queryString = self::getDeleteQueryString(!
$username, !
$contentId!
);!
!
$params = array(!
'username' => $username,!
'contentId' => $contentId,!
);!
!
$query = new Query(!
$neo4jClient,!
$queryString, !
$params!
);!
$query->getResultSet();!
}

79. Deleting Content
public static function delete($username, $contentId)!
{!
$queryString = self::getDeleteQueryString(!
$username, !
$contentId!
);!
!
$params = array(!
'username' => $username,!
'contentId' => $contentId,!
);!
!
$query = new Query(!
$neo4jClient,!
$queryString, !
$params!
);!
$query->getResultSet();!
}

80. Deleting Content
public static function delete($username, $contentId)!
{!
$queryString = self::getDeleteQueryString(!
$username, !
$contentId!
);!
!
$params = array(!
'username' => $username,!
'contentId' => $contentId,!
);!
!
$query = new Query(!
$neo4jClient,!
$queryString, !
$params!
);!
$query->getResultSet();!
}

81. Deleting Content
public static function delete($username, $contentId)!
{!
$queryString = self::getDeleteQueryString(!
$username, !
$contentId!
);!
!
$params = array(!
'username' => $username,!
'contentId' => $contentId,!
);!
!
$query = new Query(!
$neo4jClient,!
$queryString, !
$params!
);!
$query->getResultSet();!
}

82. Deleting Content: Leaf
// If leaf!
MATCH (u:User { username: { username }})-[:LASTPOST|
NEXTPOST*0..]->(c:Content { contentId: { contentId }})!
WITH c!
MATCH (c)-[r]-()!
DELETE c, r

83. Deleting Content: Leaf
// If leaf!
MATCH (u:User { username: { username }})-[:LASTPOST|
NEXTPOST*0..]->(c:Content { contentId: { contentId }})!
WITH c!
MATCH (c)-[r]-()!
DELETE c, r

84. Deleting Content: Leaf
// If leaf!
MATCH (u:User { username: { username }})-[:LASTPOST|
NEXTPOST*0..]->(c:Content { contentId: { contentId }})!
WITH c!
MATCH (c)-[r]-()!
DELETE c, r

85. Deleting Content: Leaf
// If leaf!
MATCH (u:User { username: { username }})-[:LASTPOST|
NEXTPOST*0..]->(c:Content { contentId: { contentId }})!
WITH c!
MATCH (c)-[r]-()!
DELETE c, r

86. Deleting Content: Leaf
// If leaf!
MATCH (u:User { username: { username }})-[:LASTPOST|
NEXTPOST*0..]->(c:Content { contentId: { contentId }})!
WITH c!
MATCH (c)-[r]-()!
DELETE c, r

87. Deleting Content: LASTPOST
// If last!
MATCH (u:User { username: { username }})-[lp:LASTPOST]-
>(del:Content { contentId: { contentId }})-[np:NEXTPOST]-
>(nextPost)!
CREATE UNIQUE (u)-[:LASTPOST]->(nextPost)!
DELETE lp, del, np

88. Deleting Content: LASTPOST
// If last!
MATCH (u:User { username: { username }})-[lp:LASTPOST]-
>(del:Content { contentId: { contentId }})-[np:NEXTPOST]-
>(nextPost)!
CREATE UNIQUE (u)-[:LASTPOST]->(nextPost)!
DELETE lp, del, np

89. Deleting Content: LASTPOST
// If last!
MATCH (u:User { username: { username }})-[lp:LASTPOST]-
>(del:Content { contentId: { contentId }})-[np:NEXTPOST]-
>(nextPost)!
CREATE UNIQUE (u)-[:LASTPOST]->(nextPost)!
DELETE lp, del, np

90. Deleting Content: LASTPOST
// If last!
MATCH (u:User { username: { username }})-[lp:LASTPOST]-
>(del:Content { contentId: { contentId }})-[np:NEXTPOST]-
>(nextPost)!
CREATE UNIQUE (u)-[:LASTPOST]->(nextPost)!
DELETE lp, del, np

91. Deleting Content: Other
// All other!
MATCH (u:User { username: { username }})-[:LASTPOST|
NEXTPOST*0..]->(before),!
(before)-[delBefore]->(del:Content { contentId:
{ contentId }})-[delAfter]->(after)!
CREATE UNIQUE (before)-[:NEXTPOST]->(after)!
DELETE del, delBefore, delAfter

92. Deleting Content: Other
// All other!
MATCH (u:User { username: { username }})-[:LASTPOST|
NEXTPOST*0..]->(before),!
(before)-[delBefore]->(del:Content { contentId:
{ contentId }})-[delAfter]->(after)!
CREATE UNIQUE (before)-[:NEXTPOST]->(after)!
DELETE del, delBefore, delAfter

93. Deleting Content: Other
// All other!
MATCH (u:User { username: { username }})-[:LASTPOST|
NEXTPOST*0..]->(before),!
(before)-[delBefore]->(del:Content { contentId:
{ contentId }})-[delAfter]->(after)!
CREATE UNIQUE (before)-[:NEXTPOST]->(after)!
DELETE del, delBefore, delAfter

94. Deleting Content: Other
// All other!
MATCH (u:User { username: { username }})-[:LASTPOST|
NEXTPOST*0..]->(before),!
(before)-[delBefore]->(del:Content { contentId:
{ contentId }})-[delAfter]->(after)!
CREATE UNIQUE (before)-[:NEXTPOST]->(after)!
DELETE del, delBefore, delAfter

95. Deleting Content: Other
// All other!
MATCH (u:User { username: { username }})-[:LASTPOST|
NEXTPOST*0..]->(before),!
(before)-[delBefore]->(del:Content { contentId:
{ contentId }})-[delAfter]->(after)!
CREATE UNIQUE (before)-[:NEXTPOST]->(after)!
DELETE del, delBefore, delAfter

96. Questions?

97. Thanks!
!
jeremy.kendall@graphstory.com
@JeremyKendall
http://www.graphstory.com