SQL
SQL provides state-of-the-art, high-performance SQL integration for Elixir, built to handle extreme concurrency with unmatched expressiveness and ergonomic query composition. Write safe, composable, parameterized queries directly, without translating to Ecto or any ORM.
SQL is a foreign language integration, letting you write SQL naturally while Elixir handles transactions, concurrency, and query planning for you. Unlike typical ORMs, SQL scales diagonally on the BEAM, fully leveraging multicore hardware under load.
Highlights
- Extreme Concurrency: Hundreds of processes can execute queries simultaneously without blocking pools.
- Diagonal Scaling: Utilizes BEAM concurrency to maximize throughput, far beyond traditional connection pool limits.
- Composable Queries: No need to remember
SELECTvsFROMorder—queries are fully composable via~SQL. - Safe Interpolation: Automatically parameterized queries; no need to manually handle fragments or
?. - SOTA Performance Across Languages: Benchmarks show SQL outperforming Ecto by orders of magnitude under heavy load.
- Ergonomic & Expressive: Intuitive syntax for queries, transactions, and mapping result sets.
- Streaming Large Datasets: Efficiently stream millions of rows without blocking memory or reducing concurrency.
Examples
iex(1)> email = "john@example.com" "john@example.com" iex(2)> ~SQL[from users] |> ~SQL[where email = {{email}}] |> ~SQL"select id, email" ~SQL""" select id, email from users where email = {{email}} """ iex(3)> sql = ~SQL[from users where email = {{email}} select id, email] ~SQL""" select id, email from users where email = {{email}} """ iex(4)> to_sql(sql) {"select id, email from users where email = ?", ["john@example.com"]} iex(5)> to_string(sql) "select id, email from users where email = ?" iex(6)> inspect(sql) "~SQL\"\"\"\nselect\n id, \n email\nfrom\n users\nwhere\n email = {{email}}\n\"\"\""
Transactions
SQL.transaction do Enum.to_list(~SQL"select 1") end
Transactions automatically handle nested savepoints, rollback, and commit logic, even under extreme concurrency.
Mapping Results
For custom mapping of rows:
~SQL[from users select *] |> SQL.map(fn row -> struct(User, row) end) |> Enum.to_list()
For Ecto interoperability:
~SQL[from users select *] |> SQL.map(fn row, columns -> Repo.load(User, {columns, row}) end) |> Enum.to_list()
Note:
struct(User, row)can replaceRepo.loadwhen using a custom adapter or when you don’t need full Ecto integration.
Streaming
SQL.transaction do Stream.run(~SQL"SELECT g, repeat(md5(g::text), 4) FROM generate_series(1, 5000000) AS g") end
Pool configuration
config :sql, pools: [ default: %{ username: "postgres", password: "postgres", hostname: "localhost", database: "mydatabase", adapter: SQL.Adapters.Postgres, ssl: false} ]
defmodule MyApp.Accounts do use SQL, pool: :default def list_users() do ~SQL[from users select *] |> SQL.map(fn row -> struct(User, row) end) |> Enum.to_list() end end iex(1)> MyApp.Accounts.list_users() [%User{id: 1, email: "john@example.com"}, %User{id: 2, email: "jane@example.com"}]
Compile time warning
Run mix sql.get to generate your sql.lock file for error reporting.
==> myapp Compiling 1 file (.ex) warning: the relation OPS does not exist the relation email is mentioned 2 times but does not exist the relation users does not exist ~SQL""" select email, 1 + "OPS" from users where email = 'john@example.com' """ lib/myapp.ex:18: Myapp.list_users/0 (sql 0.4.0) lib/sql.ex:225: SQL.__inspect__/3 (sql 0.4.0) lib/sql.ex:115: SQL.build/4 (elixir 1.20.0-dev) src/elixir_dispatch.erl:263: :elixir_dispatch.expand_macro_fun/7 (elixir 1.20.0-dev) src/elixir_dispatch.erl:122: :elixir_dispatch.dispatch_import/6 (elixir 1.20.0-dev) src/elixir_clauses.erl:192: :elixir_clauses.def/3 (elixir 1.20.0-dev) src/elixir_def.erl:218: :elixir_def."-store_definition/10-lc$^0/1-0-"/3 (elixir 1.20.0-dev) src/elixir_def.erl:219: :elixir_def.store_definition/10
Benchmark: Extreme Concurrency & Diagonal Scaling
SQL is not just fast—it’s a breakthrough in high-concurrency database integration. Benchmarks were run with 500 parallel processes executing transactions simultaneously on a pool of 10 connections, something most ORMs—including Ecto—cannot handle.
- SQL executes thousands of transactions per second, scaling diagonally with BEAM concurrency, fully utilizing cores without pool bottlenecks.
- Ecto, under the same conditions, falls behind by orders of magnitude, struggling with queueing, blocking, and memory overhead.
| Metric | SQL | Ecto | Improvement |
|---|---|---|---|
| Iterations/sec (IPS) | 5507.15 | 56.22 | ~98x faster |
| Memory Usage | 984 B | 17,952 B | 18x lighter |
| Reductions Count | 0.092 K | 1.56 K | 17x fewer reductions |
You can find benchmark results here or run mix sql.bench
Installation
The package can be installed by adding sql to your list of dependencies in mix.exs:
def deps do [ {:sql, "~> 0.4.0"} ] end
Documentation can be found at https://hexdocs.pm/sql.