ODBCAdapter

An ActiveRecord ODBC adapter. Pattern has made some updates to get this working with Rails 6 as forked from repo was not actively being maintained to do so.

This adapter will work for basic queries for most DBMSs out of the box, without support for migrations. Full support is built-in for MySQL 5 and PostgreSQL 9 databases. You can register your own adapter to get more support for your DBMS using the ODBCAdapter.register function.

A lot of this work is based on OpenLink's ActiveRecord adapter which works for earlier versions of Rails.

Installation

Ensure you have the ODBC driver installed on your machine. You will also need the driver for whichever database to which you want ODBC to connect.

Add this line to your application's Gemfile:

gem 'odbc_adapter'

And then execute:

$ bundle

Or install it yourself as:

$ gem install odbc_adapter

Usage

Configure your database.yml by either using the dsn option to point to a DSN that corresponds to a valid entry in your ~/.odbc.ini file:

development:
  adapter:  odbc
  dsn: MyDatabaseDSN

or by using the conn_str option and specifying the entire connection string:

development:
  adapter: odbc
  conn_str: "DRIVER={PostgreSQL ANSI};SERVER=localhost;PORT=5432;DATABASE=my_database;UID=postgres;"

ActiveRecord models that use this connection will now be connecting to the configured database using the ODBC driver.

Testing

To run the tests, you'll need the ODBC driver as well as the connection adapter for each database against which you're trying to test. Then run DSN=MyDatabaseDSN bundle exec rake test and the test suite will be run by connecting to your database.

Testing Using a Docker Container Because ODBC on Mac is Hard

Tested on Sierra.

Run from project root:

bundle package
docker build -f Dockerfile.dev -t odbc-dev .

# Local mount mysql directory to avoid some permissions problems
mkdir -p /tmp/mysql
docker run -it --rm -v $(pwd):/workspace -v /tmp/mysql:/var/lib/mysql odbc-dev:latest

# In container
docker/test.sh

Datatype References

Reference https://docs.snowflake.com/en/sql-reference/intro-summary-data-types

https://github.com/rails/rails/blob/main/activerecord/lib/active_record/connection_adapters/abstract_adapter.rb#L877-L908

["number",
 "decimal",
 "numeric",
 "int",
 "integer",
 "bigint",
 "smallint",
 "tinyint",
 "byteint",
 "float",
 "float4",
 "float8",
 "double",
 "real",
 "varchar",
 "char",
 "character",
 "string",
 "text",
 "binary",
 "varbinary",
 "boolean",
 "date",
 "datetime",
 "time",
 "timestamp",
 "timestamp_ltz",
 "timestamp_ntz",
 "timestamp_tz",
 "variant",
 "object",
 "array",
 "geography",
 "geometry"]

Possible mapping from chatgpt

Snowflake Data Type	Ruby ActiveRecord Type	PostgreSQL Type
number	:decimal	numeric
decimal	:decimal	numeric
numeric	:decimal	numeric
int	:integer	integer
integer	:integer	integer
bigint	:bigint	bigint
smallint	:integer	smallint
tinyint	:integer	smallint
byteint	:integer	smallint
float	:float	double precision
float4	:float	real
float8	:float	double precision
double	:float	double precision
real	:float	real
varchar	:string	character varying
char	:string	character
character	:string	character
string	:string	character varying
text	:text	text
binary	:binary	bytea
varbinary	:binary	bytea
boolean	:boolean	boolean
date	:date	date
datetime	:datetime	timestamp without time zone
time	:time	time without time zone
timestamp	:timestamp	timestamp without time zone
timestamp_ltz	:timestamp	timestamp without time zone
timestamp_ntz	:timestamp	timestamp without time zone
timestamp_tz	:timestamp	timestamp with time zone
variant	:jsonb	jsonb
object	:jsonb	jsonb
array	:jsonb	jsonb
geography	:st_point, :st_polygon,	geography
	:st_multipolygon
geometry	:st_point, :st_polygon,	geometry
	:st_multipolygon

Contributing

Bug reports and pull requests are welcome on GitHub at https://github.com/localytics/odbc_adapter.

License

The gem is available as open source under the terms of the MIT License.