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SQL (Relational Databasw (Query - checking info (SELECT * FROM celebs; -…

- - - - Data Types
        
        Integer, a positive or negative whole number
        
        Text, a text string
        
        Date, the date formatted as YYYY-MM-DD for the year, month, and day
        
        Real, a decimal value
      - CREATE TABLE celebs (id INTEGER, name TEXT, age INTEGER);
      - INSERT INTO celebs (id, name, age) VALUES (1, 'Justin Bieber', 21);\
      - ALTER TABLE celebs ADD COLUMN twitter_handle TEXT;
      - multiple tables
        
        related by primary and foreign keys
        
        cross join
        
        Inner Join
        
        SELECT * specifies the columns our result set will have. Here, we want to include every column in both tables.
        FROM albums specifies the first table we are querying.
        JOIN artists ON specifies the type of join we are going to use as well as the name of the second table.
        Here, we want to do an inner join and the second table we want to query is artists.
        albums.artist_id = artists.id is the join condition that describes how the two tables are related to each other.
        Here, SQL uses the foreign key column artist_id in the albums table to match it with exactly one row in the artists table with the same value in the id column. We know it will only match one row in the artists table because id is the PRIMARY KEY of artists.
        
        SELECT albums.name, albums.year, artists.name FROM albums, artists;
        
        left join
        
        everything plus nulls for em[ties
        
        AS is a keyword in SQL that allows you to rename a column or table using an alias.
        
        SELECT
        
        albums.name AS 'Album',