# Developing odbc

This vignette is intended to help developers of the R package install needed dependencies.

While the odbc package contains some documentation on how to install and configure database drivers in `vignette("setup")`, the documentation assumes that users are connecting to databases that have already been set up. In order to test package functionality, though, odbc sets up small example database deployments.

For the most part, this vignette assumes a MacOS system with aarch64 (e.g. M1 or M2) architecture. For Linux example code, see `.github/workflows/db.yaml`, and for Windows, see `.github/workflows/db-windows.yml`.

## PostgreSQL

On MacOS, install PostgreSQL with:

    brew install postgresql@14

You’ll also need to install and configure the PostgreSQL driver `psqlodbc`; see `vignette("setup")` to learn more.

To launch a PostgreSQL server locally, run:

    brew services start postgresql@14

Next, create a database called “test” (or by whatever name is in the entry `Database` in your `odbc.ini` file):

    createdb test

At this point, you should be able to connect to PostgreSQL through the R interface. Connect with:

    postgres <- dbConnect(odbc(), "PostgreSQL")

where `"PostgreSQL"` is replaced with whatever DSN you’ve configured.

## MySQL

First, installing MySQL with Homebrew:

    brew install mysql@8.2

MariaDB drivers are compatible with MySQL and are more easily installed than MySQL drivers themselves in most cases. To install the MariaDB driver:

    brew install mariadb-connector-odbc

Then, link the MariaDB driver with your MySQL data source name. That is, with the driver name `[MariaDB]` configuring your MariaDB install in `odbcinst.ini`, the first lines of your `odbc.ini` entry should look something like:

    [MySQL]
    Driver = MariaDB

After running `brew services start mysql` if needed, and confirming that the database is running with `brew services info mysql`, you should be able to:

    library(odbc)
    dbConnect(odbc(), "MySQL")

The second argument `"MySQL"` refers to the data source name configured above.

## SQL Server test setup

To run Microsoft SQL Server on aarch64 (e.g. M1 or M2) MacOS, you will need:

- Docker 4.16 or higher
- MacOS 13 Ventura (or higher)

If needed, install Docker with:

    brew install --cask docker

The Docker Desktop app provides a GUI to monitor deployed Docker containers and lives in `Docker.app > Show Package Contents > Contents > MacOS > Docker Desktop.app`.

To install the SQL Server ODBC driver and (optional) command line tool, use:

    brew tap microsoft/mssql-release https://github.com/Microsoft/homebrew-mssql-release
    brew install microsoft/mssql-release/msodbcsql18 microsoft/mssql-release/mssql-tools18

The `odbc.ini` entry should look something like:

    [MicrosoftSQLServer]
    driver = ODBC Driver 18 for SQL Server
    Server = 127.0.0.1
    port = 1433
    Encrypt = no

With the driver name in `odbcinst.ini` being `[ODBC Driver 18 for SQL Server]`.

With docker and the needed driver installed, deploy the container with:

    sudo docker run \
      --platform linux/amd64 \
      -e "ACCEPT_EULA=Y" \
      -e 'MSSQL_SA_PASSWORD=BoopBop123!' \
      -p 1433:1433 \
       --name sql1 \
       --hostname sql1 \
       -d mcr.microsoft.com/mssql/server:2022-latest

The `--platform` tag is correct for M1; if you see `Status: Exited (1)` in Docker Desktop or a warning about incompatible architectures, navigate to `Settings > General` and ensure that `Use Rosetta for x86/amd64 emulation on Apple Silicon` is checked.

To connect via odbc, we need to pass the UID and PWD via the connection string; configuring those arguments via `odbc.ini` is not permitted. With the container deployed as above, the connection arguments would be:

    con <- dbConnect(
      odbc::odbc(),
      dsn = "MicrosoftSQLServer",
      uid = "SA",
      pwd = "BoopBop123!"
    )

Then do some configuration of the server to add a testuser and create the test database

To configure a server to add a testing user and create a test database:

    # Add a test user, but currently unused
    dbExecute(con, "USE test")
    dbExecute(con, "EXEC sp_configure 'contained database authentication', 1")
    dbExecute(con, "RECONFIGURE")
    dbExecute(con, "alter database test set containment = partial")
    dbExecute(con, "CREATE USER testuser with password = 'BoopBop123!'")
    dbExecute(con, "GRANT CONTROL TO testuser")
    dbExecute(con, "DROP USER testuser")

    # Create a test database
    dbExecute(con, "CREATE DATABASE test")

On Linux, create a docker container with:

    docker run -v "$(pwd)":"/opt/$(basename $(pwd))":delegated --security-opt=seccomp:unconfined --link sql1 -it rstudio/r-base:3.6.1-bionic /bin/bash

Then run:

    curl https://packages.microsoft.com/keys/microsoft.asc | apt-key add -
    #Ubuntu 18.04
    curl https://packages.microsoft.com/config/ubuntu/18.04/prod.list > /etc/apt/sources.list.d/mssql-release.list

    apt-get update
    ACCEPT_EULA=Y apt-get install -y msodbcsql17
    apt-get install -y unixodbc-dev

The resulting `odbc.ini` file will look something like:

    [MicrosoftSQLServer]
    driver = ODBC Driver 17 for SQL Server
    Server = sql1
    port = 1433
    Database = test

## SQLite

MacOS provides SQLite natively. With the SQLite odbc driver installed (see `vignette("setup")` if needed), run:

    library(odbc)
    dbConnect(odbc(), "SQLite")

The above example assumes the configured SQLite DSN is called `"SQLite"`.

## Oracle

A huge pain.

Get the DB container:

    docker login

    docker pull store/oracle/database-enterprise:12.2.0.1

Start the container:

    docker run -d -it --name oracle_db -P store/oracle/database-enterprise:12.2.0.1

The `-P` is important to set up the port forwarding from the docker container.

Then, query the port and edit the ports in `tnsnames.ora`:

    docker port oracle_db

The contents of `snsnames.ora` should look like:

    ORCLCDB=(DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=127.0.0.1)(PORT=32769))
        (CONNECT_DATA=(SERVER=DEDICATED)(SERVICE_NAME=ORCLCDB.localdomain)))
    ORCLPDB1=(DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=127.0.0.1)(PORT=32769))
        (CONNECT_DATA=(SERVER=DEDICATED)(SERVICE_NAME=ORCLPDB1.localdomain)))

Ensure that the current working directly is set appropriately.

Then, to add a new user to the database:

    docker exec -it oracle_db bash -c "source /home/oracle/.bashrc; sqlplus SYS/Oradoc_db1 AS SYSDBA"

    alter session set "_ORACLE_SCRIPT"=true;

    create user test identified by 12345;

    GRANT ALL PRIVILEGES TO TEST;

Finally, in R:

    Sys.setenv("TNS_ADMIN" = getwd())
    con <- dbConnect(odbc::odbc(), "OracleODBC-19")

## Snowflake

To obtain a Snowflake account:

- If you’re a Posit employee, reach out to James Blair.
- If you’re not affiliated with Posit, sign up for a free trial.

Install drivers using the instructions on the Snowflake documentation. For MacOS, feel free to ignore sections noting that iODBC is required.

On MacOS and Linux:

- Locate your `simba.snowflake.ini` file, likely in `opt/snowflake/`. You will need `sudo` access to edit it.
  - Change `DriverManagerEncoding` to `UTF-16`.
  - Change the uncommented `ODBCInstLib` entry to the path of your unixODBC install.
- In the Snowflake UI, navigate to Worksheets, make a new worksheet using the blue “+” button in the top right-hand corner, and run the line `SELECT SYSTEM$ALLOWLIST()`. In the output, copy the URL corresponding to `"type":"SNOWFLAKE_DEPLOYMENT"`. This Deployment URL should look like a random string, an AWS region, and the snowflake API URL, e.g. `wmc39401.us-east-1.snowflakecomputing.com`.

The `odbc.ini` file should look like:

    [Snowflake]
    Driver      = Snowflake
    Description =
    uid         = <uid>
    server      = <deployment-url>

The above assumes `Driver = Snowflake` is configured in `odbcinst.ini`. Then, connect by supplying the password as an argument:

    con <- dbConnect(odbc(), dsn = "Snowflake", pwd = Sys.getenv("snowflakePass"))

In the above, the password has been set as `Sys.setenv(snowflakePass = "actualPass")`.

## RODBC

We need to install the RODBC package for benchmarking in the vignette `vignette("benchmarks")`. The CRAN version of RODBC uses iODBC, so to use unixODBC we need to recompile it from source, specifying the odbc manager explicitly:

    install.packages("RODBC", type = "source", INSTALL_opts="--configure-args='--with-odbc-manager=odbc'")