part 1: database script

db_skript.sql

+CREATE TABLE twitter_user (
+	id  				serial PRIMARY KEY
+,	handle   			text NOT NULL UNIQUE
+);
+
+CREATE TABLE hashtag (
+  id  			serial PRIMARY KEY
+, hash_tag_text     	text NOT NULL
+);
+
+CREATE TABLE tweet (
+  id			serial PRIMARY KEY
+, retweet_count    	int NOT NULL DEFAULT 0
+, favorite_count    	int NOT NULL DEFAULT 0
+, tweet_text    	text NOT NULL
+, tweet_time    	timestamp NOT NULL
+, original_author      	text
+, CONSTRAINT vorgaenger_ID FOREIGN KEY(id) REFERENCES tweet(id)
+);
+
+CREATE TABLE tweet_hat_hashtag (
+  FK_tweet integer
+, FK_hashtag integer
+, hashtag_text  text NOT NULL
+, FOREIGN KEY(FK_tweet) REFERENCES tweet(id) ON UPDATE CASCADE ON DELETE CASCADE
+, FOREIGN KEY(FK_hashtag) REFERENCES hashtag (id) ON UPDATE CASCADE ON DELETE CASCADE
+, PRIMARY KEY (FK_tweet, FK_hashtag)
+);
+