postgres - working with vector

Here is a  simple tutorial how to work with postgres vector. We will create a table and one of its column embedding uses a embedding dimension of 2. 

CREATE TABLE doctest (

    id SERIAL PRIMARY KEY,

    content TEXT,

    embedding vector(2) -- OpenAI's ada-002 embedding size

);

To insert value into the table 

INSERT INTO doctest (content, embedding) VALUES ('test', '[1.23,1.245]')

INSERT INTO doctest (content, embedding) VALUES ('test7', '[7, 10]')

To select 

   SELECT content, 1 - (embedding <=> '[7, 9]') AS similarity

    FROM doctest

    ORDER BY similarity DESC

    LIMIT 1;

And gives you the output here:

If you make another search

   SELECT content, 1 - (embedding <=> '[1.23, 1.3]') AS similarity

    FROM doctest

    ORDER BY similarity DESC

    LIMIT 1;