# Tds

MSSQL / TDS Database driver for Elixir.

This is an alpha version that currently supports Ecto 2.0. It has implemented the [db_connection](https://github.com/elixir-ecto/db_connection) behaviour, and added support for transactions and prepared queries.
Please check out the issues for a more complete overview. This branch should not yet be considered stable or used in production.

## Usage

Add Tds as a dependency in your `mix.exs` file.

```elixir
def deps do
  [{:tds, "~> 1.0.4"} ]
end
```

After you are done, run `mix deps.get` in your shell to fetch and compile Tds. Start an interactive Elixir shell with `iex -S mix`.

```iex
iex> {:ok, pid} = Tds.start_link([hostname: "localhost", username: "test_user", password: "test_password", database: "test_db", port: 4000])
{:ok, #PID<0.69.0>}
iex> Tds.query!(pid, "SELECT 'Some Awesome Text' AS MyColumn", [])
%Tds.Result{columns: ["MyColumn"], rows: [{"Some Awesome Text"}], num_rows: 1}}
iex> Tds.query!(pid, "INSERT INTO MyTable (MyColumn) VALUES (@my_value)", [%Tds.Parameter{name: "@my_value", value: "My Actual Value"}])
%Tds.Result{columns: nil, rows: nil, num_rows: 1}}
```

## Features

  * Automatic decoding and encoding of Elixir values to and from MSSQL's binary format
  * Supports TDS Version 7.3, 7.4

## Connecting to SQL Instances
Tds Supports sql instances by passing ```instance: "instancename"``` to the connection options.



## Data representation

    TDS             Elixir
    ----------      ------
    NULL            nil
    bool            true | false
    char            "é"
    int             42
    float           42.0
    text            "text"
    binary          <<42>>
    numeric         #Decimal<42.0> *
    date            {2013, 10, 12}
    time            {0, 37, 14}
    datetime	      {{2013, 10, 12}, {0, 37, 14}}
    uuid            <<160,238,188,153,156,11,78,248,187,109,107,185,189,56,10,17>>

All data types will be supported, unsupported types currently are *User Defined Types*, xml

## Contributing

To contribute you need to compile Tds from source and test it:

```
$ git clone https://github.com/livehelpnow/tds.git
$ cd tds
$ mix test
```

The tests require your sql server database to be present on localhost. In case you are unable to run local instance of SQL server either using local installation on [windows](https://docs.microsoft.com/en-us/sql/database-engine/install-windows/install-sql-server-from-the-installation-wizard-setup) or [linix](https://docs.microsoft.com/en-us/sql/linux/sql-server-linux-setup), docker image for [linux](https://hub.docker.com/r/microsoft/mssql-server-linux/) 
You will need sqlcmd command line tools for some operations in test. Setup instructions can be found [here](https://docs.microsoft.com/en-us/sql/linux/sql-server-linux-setup-tools)

Additionally SQL authentication needs to be used for connecting and testing. Check config/test.exs file for credentials used in unit testing.

##Special Thanks

Thanks to ericmj, this driver takes a lot of inspiration from postgrex.
https://github.com/ericmj/


Also thanks to everyone in the Elixir Google group and on the Elixir IRC Channel


## License

   Copyright 2014, 2015, 2017 LiveHelpNow

   Licensed under the Apache License, Version 2.0 (the "License");
   you may not use this file except in compliance with the License.
   You may obtain a copy of the License at

       http://www.apache.org/licenses/LICENSE-2.0

   Unless required by applicable law or agreed to in writing, software
   distributed under the License is distributed on an "AS IS" BASIS,
   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   See the License for the specific language governing permissions and
   limitations under the License.