PostgreSQL mencari kata yang mirip dan Rank similarity

 You will match against a tsquery to determine if the phrase "Astounding Drama" leads to more rentals per month. Next, create a new column using the similarity function to rank the film descriptions based on this phrase.

• Select the title and description for all DVDs from the film table.
• Perform a full-text search by converting the description to a tsvector and match it to the phrase 'Astounding & Drama' using a tsquery in the WHERE clause.

• Add a new column that calculates the similarity of the description with the phrase 'Astounding Drama'.
• Sort the results by the new similarity column in descending order.

-- Select the title and description columns

SELECT  

  title, 

  description 

FROM 

  film

WHERE 

  -- Match "Astounding Drama" in the description

  to_tsvector(description) @@ 

  to_tsquery('Astounding & Drama');

title	description
COWBOY DOOM	A Astounding Drama of a Boy And a Lumberjack who must Fight a Butler in A Baloon
BIKINI BORROWERS	A Astounding Drama of a Astronaut And a Cat who must Discover a Woman in The First Manned Space Station
CAMPUS REMEMBER	A Astounding Drama of a Crocodile And a Mad Cow who must Build a Robot in A Jet Boat
ENCINO ELF	A Astounding Drama of a Feminist And a Teacher who must Confront a Husband in A Baloon
GLASS DYING	A Astounding Drama of a Frisbee And a Astronaut who must Fight a Dog in Ancient Japan

SELECT 

  title, 

  description, 

  -- Calculate the similarity

  similarity(description, 'Astounding Drama')

FROM 

  film 

WHERE 

  to_tsvector(description) @@ 

  to_tsquery('Astounding & Drama') 

ORDER BY 

  similarity(description, 'Astounding Drama') DESC

title	description	similarity
COWBOY DOOM	A Astounding Drama of a Boy And a Lumberjack who must Fight a Butler in A Baloon	0.246377
GLASS DYING	A Astounding Drama of a Frisbee And a Astronaut who must Fight a Dog in Ancient Japan	0.239437
CAMPUS REMEMBER	A Astounding Drama of a Crocodile And a Mad Cow who must Build a Robot in A Jet Boat	0.236111
ENCINO ELF	A Astounding Drama of a Feminist And a Teacher who must Confront a Husband in A Baloon	0.22973
BIKINI BORROWERS	A Astounding Drama of a Astronaut And a Cat who must Discover a Woman in The First Manned Space Station	0.195402