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RAILS_ENV | = | -> { (Rails.env if defined?(Rails.env)) || ENV["RAILS_ENV"] || ENV["RACK_ENV"] } |
DEFAULT_ENV | = | -> { RAILS_ENV.call || "default_env" } |
Returns true
if Active Record is connected.
Returns the connection currently associated with the class. This can also be used to “borrow” the connection to do database work unrelated to any of the specific Active Records.
Returns the configuration of the associated connection as a hash:
ActiveRecord::Base.connection_config
# => {pool: 5, timeout: 5000, database: "db/development.sqlite3", adapter: "sqlite3"}
Please use only for reading.
Establishes the connection to the database. Accepts a hash as input where
the :adapter
key must be specified with the name of a database
adapter (in lower-case) example for regular databases (MySQL, Postgresql,
etc):
ActiveRecord::Base.establish_connection(
adapter: "mysql",
host: "localhost",
username: "myuser",
password: "mypass",
database: "somedatabase"
)
Example for SQLite database:
ActiveRecord::Base.establish_connection(
adapter: "sqlite3",
database: "path/to/dbfile"
)
Also accepts keys as strings (for parsing from YAML for example):
ActiveRecord::Base.establish_connection(
"adapter" => "sqlite3",
"database" => "path/to/dbfile"
)
Or a URL:
ActiveRecord::Base.establish_connection(
"postgres://myuser:mypass@localhost/somedatabase"
)
In case ActiveRecord::Base.configurations
is set (Rails
automatically loads the contents of config/database.yml into it), a symbol
can also be given as argument, representing a key in the configuration
hash:
ActiveRecord::Base.establish_connection(:production)
The exceptions AdapterNotSpecified, AdapterNotFound and ArgumentError may be returned on an error.
# File activerecord/lib/active_record/connection_handling.rb, line 47 def establish_connection(spec = nil) spec ||= DEFAULT_ENV.call.to_sym resolver = ConnectionAdapters::ConnectionSpecification::Resolver.new configurations spec = resolver.spec(spec) unless respond_to?(spec.adapter_method) raise AdapterNotFound, "database configuration specifies nonexistent #{spec.config[:adapter]} adapter" end remove_connection connection_handler.establish_connection self, spec end