Relational Databases

Using Information Schema

SELECT 
    table_schema, 
    table_name
FROM 
    information_schema.tables;

Taking the look at the columns of a certain table using the Information Schema

SELECT
    table_name, 
    column_name,
    data_type
FROM
    information_schema.tables
WHERE
    table_name = 'pg_config';

Creating new tables with CREATE TABLE

CREATE TABLE table_name (
    column_a data_type,
    column_b data_type,
    column_c data_type
);

Example:

CREATE TABLE weather (
      clouds text, 
      temperature numeric,
      weather_station char(5)
  )

INSERT INTO statement

INSERT INTO table_name (column_a, column_b)
VALUES ("value_a", "value_b");

RENAME a column

ALTER TABLE table_name
RENAME COLUMN old_name TO new_name;

DROP a column

ALTER TABLE table_name
DROP COLUMN column_name;

Constraints