MSSQL is supported in Ecto 2 through tds_ecto or mssql_ecto, where mssql_ecto performs much better in our experience.
There is a however caveat when using parameterized queries, which seems quite undocumented:
This query will fail in both tds_ecto and mssql_ecto
sql = "select * from users where name = $1"
This will work in tds_ecto
sql = "select * from users where name = @1"
This will work in mssql_ecto
sql = "select * from users where name = ?1"
