#Day 13
###Date In pry
require 'date' today = Date.today today.tuesday?
birthday = Date.new(1990/10/18) age = today - birthdate
###Postgres
In the terminal, start PostGres with "psql" ans type "\l" to have a list of our databases, "\c database name" to connect to a database.
"\d" to check relations.
####Datatypes
"bigint" store a number 2^64. Range of numbers from -2^32 to 2^32 "bigserial" "box" "varchar(7)" "char" "date" | "timestamp" will keep track of when you created a record and last time it was updated. "integer" "money" "text" "xml" - particular kind of text "json"
primary keys / foreign keys --> primary keys are the keys used in the pimary tables and foreign keys are the same keys alled in another table.