What does the Heroku database URL "HEROKU_POSTGRESQL_WHITE_URL" mean?

Question

What is a “value” - if any - when is the database URL called HEROKU_POSTGRESQL_WHITE_URL? I saw other names in the Heroku documentation such as "HEROKU_POSTGRESQL_PURPLE_URL", HEROKU_POSTGRESQL_CHARCOAL_URL, ...

Does this always mean your primary database or the first database? I'd like to know.

$ heroku pg:info
=== HEROKU_POSTGRESQL_WHITE_URL (DATABASE_URL)
Plan:               Standard 0
Status:             Available
Data Size:          491.9 MB
Tables:             22
PG Version:         9.3.5
....

Answer 1

Colors are randomly selected and exist uniquely in the application area into which the database was created. In different applications, colors do not matter or correlate.

, 2 4 , 3 :

• my_awesome_application
  • HEROKU_POSTGRESQL_WHITE_URL
  • HEROKU_POSTGRESQL_RED_URL
• my_other_thing
  • HEROKU_POSTGRESQL_BLUE_URL
  • HEROKU_POSTGRESQL_WHITE_URL

db:info (DATABASE_URL) - , ( - ). heroku config, -

HEROKU_POSTGRESQL_WHITE_URL=postgres://path.to:a/db
DATABASE_URL=<the same value WHITE has>

, , , config URL-. , pg:info , .