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Installation/Run

docker-compose up [-d]

Durch das Importieren der Daten kann der Startup bis zu 30 Minuten dauern.

Cassandra

Die Befehle können in Cassandra Web mit der Adresse localhost:3000 oder im Docker Container mit:

sudo docker exec -it cass1 cqlsh

Hinweis: Die MATERIALZIED VIEWS und CUSTOM INDEX sind bereits im Startup-Skript erstellt und müssen nicht erneut ausgeführt werden.

Queries

Alle Queries finden Sie auch hier.

Auflisten der Posts, die von einem Account gemacht wurden, bzw. ihm zugeordnet wurden
```
 SELECT content FROM twitter.tweets where author_id = 233248636;
```

Finden der 100 Accounts mit den meisten Followern

 CREATE MATERIALIZED VIEW twitter.most_follows AS 
 	SELECT user_id, follower_len from twitter.user_stats 
 	WHERE user_id is not null and follower_len is not null 
 	PRIMARY KEY (follower_len,user_id);

 SELECT user_id FROM twitter.most_follows LIMIT 100;

Top 100 most followed accounts: [817268, 173732041, 14506809, 158804228, 358775055, 45416789, 302282272, 65913144, 261001122, 14246001, 7702232, 101204352, 280365428, 15439395, 26929220, 46537966, 32774989, 2367911, 7429892, 88097807, 274153775, 41147062, 127973392, 10350, 12127832, 18666844, 279787626, 14511951, 116036694, 225784456, 270449528, 63796828, 22784458, 364917755, 15693493, 17346342, 28933226, 7872262, 14180231, 100581193, 88323281, 131029775, 25952851, 14692604, 21681252, 309366491, 25376226, 22705686, 188108667, 18715024, 3829151, 41172837, 92319025, 24081780, 15102849, 83943787, 15680204, 7846, 184097849, 7377812, 204317520, 24641194, 14691709, 112939321, 7081402, 153226312, 14269220, 94414805, 108811740, 1065921, 221829166, 116952434, 15222083, 6608332, 17759701, 16098603, 7860742, 20471349, 6519522, 19040580, 14536491, 197504076, 12611642, 36198161, 3840, 22841103, 440963134, 20273398, 17092592, 13348, 17093617, 22679419, 208132323, 18776017, 15846407, 18581803, 5442012, 813286, 3359851, 59804598]

Finden der 100 Accounts, die den meisten der Accounts folgen, die in 2. gefunden wurden

followed_accs = session.execute(f'SELECT follower_id FROM twitter.follower_relation WHERE user_id IN {tuple(most_follows)};')
_list = list()
for row in followed_accs:
    _list.append(row[0])

followed_top_100 = Counter(_list).most_common(100)
print("100 accounts that follow the most of the accounts found in 2)",followed_top_100)

100 accounts that follow the most of the accounts found in 2) [(3359851, 47), (7860742, 47), (15913, 45), (7861312, 45), (16098603, 43), (18776017, 41), (10350, 39), (48485771, 39), (22679419, 38), (3443591, 37), (18581803, 37), (18927441, 37), (26281970, 37), (7872262, 36), (24742040, 36), (5442012, 36), (10671602, 35), (11928542, 35), (14922225, 35), (16453996, 35), (21681252, 35), (14589257, 34), (15853668, 34), (9451052, 34), (65913144, 34), (14269220, 34), (15234657, 34), (17092592, 34), (59804598, 34), (87764480, 34), (40981798, 34), (16475194, 34), (16464746, 33), (93905958, 33), (20152005, 33), (42361118, 33), (36629388, 33), (18666844, 32), (19413393, 32), (12127832, 32), (14180231, 32), (14983833, 32), (25026165, 32), (18742444, 32), (29758446, 31), (20880546, 31), (116952434, 31), (30207757, 31), (21195122, 31), (43003845, 31), (22784458, 30), (19040580, 30), (14691709, 30), (24004172, 30), (1065921, 30), (26280712, 30), (43170475, 30), (22462180, 30), (7846, 29), (1183041, 29), (3040621, 29), (7377812, 29), (34428380, 29), (20273398, 28), (14230524, 28), (15222083, 28), (24641194, 28), (83943787, 28), (36198161, 28), (14536491, 28), (813286, 27), (12611642, 27), (29514951, 27), (31353077, 27), (18996905, 27), (14471778, 27), (15838599, 27), (16112634, 27), (17526132, 27), (17759701, 27), (31331740, 27), (25952851, 27), (84043660, 27), (9431932, 27), (20397258, 27), (127973392, 27), (16674726, 27), (116036694, 27), (972651, 26), (13687132, 26), (4068821, 26), (7702232, 26), (6080022, 26), (17224642, 26), (20935355, 26), (24081780, 26), (26033920, 26), (28933226, 26), (43933017, 26), (101633415, 26)]

Auflisten der Informationen für die persönliche Startseite eines beliebigen Accounts (am besten mit den in 2. gefundenen Accounts ausprobieren); die Startseite soll Folgendes beinhalten (als getrennte Queries umsetzen):
- 4.1 und 4.2 die Anzahl der Follower && die Anzahl der verfolgten Accounts
  
  SELECT follower_len, follows_len FROM twitter.user_stats WHERE user_id = 233248636; //check user_id can be changed
- 4.3 wahlweise die 25 neusten (zeitbasiert) oder die 25 beliebtesten Posts (like-basiert) der verfolgten Accounts (per DB-Abfrage)
25 neuste
```
 CREATE MATERIALIZED VIEW twitter.start_view_new AS
 SELECT user_id_x,follower_id,number_of_likes,number_of_shares,date_time,name,author,content,id FROM twitter.user
 WHERE user_id_x IS NOT NULL AND follower_id IS NOT NULL AND date_time IS NOT NULL AND id IS NOT NULL
 PRIMARY KEY ((user_id_x),date_time,follower_id,id);

 SELECT * FROM twitter.start_view_new WHERE user_id_x = 172883064 ORDER BY date_time DESC LIMIT 25;
```
25 beliebteste
```
 // To order by the 25 most number_of_like is to our knowledge not possible with the current dataschema
 CREATE MATERIALIZED VIEW twitter.start_view_like AS
 SELECT user_id_x,follower_id,number_of_likes,number_of_shares,date_time,author,name,content,id FROM twitter.user
 WHERE user_id_x IS NOT NULL AND follower_id IS NOT NULL AND number_of_likes IS NOT NULL AND id IS NOT NULL
 PRIMARY KEY ((user_id_x),number_of_likes,follower_id,id);

 SELECT * FROM twitter.start_view_like WHERE user_id_x = 172883064 ORDER BY number_of_likes DESC LIMIT 25;
```
- 4.4 Caching der Posts für die Startseite (vgl. 4), erfordert einen sog. Fan-Out in den Cache jedes Followers beim Schreiben eines neuen Posts
  
  CREATE MATERIALIZED VIEW twitter.start_view_user1 AS SELECT follower_id,number_of_likes,date_time,author,name,content,id FROM twitter.user WHERE user_id_x IS NOT NULL AND user_id_x=172883064 AND follower_id IS NOT NULL AND number_of_likes IS NOT NULL AND id IS NOT NULL PRIMARY KEY ((user_id_x),number_of_likes,follower_id,id); // # order by need partion key in WHERE SELECT * from twitter.start_view_taylor WHERE user_id_x=172883064 ORDER BY number_of_likes DESC LIMIT 25; // INSERT new tweet INSERT INTO twitter.user (user_id_x,follower_id,name,author ,content ,country ,date_time ,id ,language ,latitude ,longitude ,number_of_likes ,number_of_shares ,user_id_y) VALUES (172883064, 233248636, 'NoName','taylorswift12', 'Hallo there BDEA','DE', dateof(now()), 'NoID', 'de', 48, 48, 10000000, 0, 0);
  
  INSERT INTO twitter.tweets(author, content, country, date_time, id, language, latitude, longitude, number_of_likes, number_of_shares ,author_id) VALUES ('taylorswift12', 'Hallo there BDEA','DE', dateof(now()), 'NoID', 'de', 48, 48, 10000000, 0, 233248636);
- 4.5 Auflisten der 25 beliebtesten Posts, die ein geg. Wort enthalten (falls möglich auch mit UND-Verknüpfung mehrerer Worte)
  
  CREATE CUSTOM INDEX search_in ON twitter.tweets (content) USING 'org.apache.cassandra.index.sasi.SASIIndex' WITH OPTIONS = { 'mode': 'CONTAINS', 'analyzer_class': 'org.apache.cassandra.index.sasi.analyzer.NonTokenizingAnalyzer', 'case_sensitive': 'false' }; SELECT * from twitter.tweets WHERE content LIKE '%world%' limit 25;

7.7 KiB Raw Blame History

Installation/Run

Cassandra

Queries

7.7 KiB

Raw Blame History