SQL, Mongo & Redis

All databases open with db_open and are gated by require db(scope). Three families: SQL (SQLite/Postgres/MySQL), documents (MongoDB, mongo_), key-value (Redis, redis_). All drivers are pure-Rust (single static binary).

-- Doc example: SQL over SQLite in-memory (real, no server). Same API for Postgres/MySQL.
intent: "doc example: SQL"
require db(":memory:")

db_open(":memory:", "memory")
sql_exec("CREATE TABLE demo (n TEXT)")
sql_exec("INSERT INTO demo VALUES (?)", ["it works"])
print("sql demo → " + (sql("SELECT n FROM demo")[0])["n"])
db_close()

test "create, parameterized insert, query"
    db_open(":memory:", "memory")
    sql_exec("CREATE TABLE items (name TEXT, price REAL)")
    sql_exec("INSERT INTO items VALUES (?, ?)", ["Laptop", 999])
    sql_exec("INSERT INTO items VALUES (?, ?)", ["Mouse", 25])
    let rows be sql("SELECT name, price FROM items WHERE price > ? ORDER BY price DESC", [50])
    assert_eq(length(rows), 1)
    assert_eq(name of (rows[0]), "Laptop")
    db_close()

SQL (SQLite / Postgres / MySQL)

require db("./store.db")
db_open("./store.db")                 -- file → SQLite. ":memory:" with mode "memory". postgres:// / mysql://
sql_exec("INSERT INTO users (name) VALUES (?)", ["Ada"])   -- parameterized (safe)
let rows be sql("SELECT * FROM users WHERE id = ?", [1])
give paged("SELECT * FROM users ORDER BY id")              -- pagination for a route handler

Placeholders are always ? (Postgres rewrites to $n internally; MySQL uses ? natively). bytes columns round-trip to BLOB/BYTEA byte-exactly.

MongoDB (documents)

require db("mongodb://localhost/appdb")
db_open("mongodb://host:27017/appdb")
let id be mongo_insert("users", {"name": "Ana", "age": 30})
let adults be mongo_find("users", {"age": {"$gte": 18}}, {"sort": {"age": -1}})

Redis (key-value / cache / structures)

require db("redis://localhost")
db_open("redis://localhost:6379")
redis_set("session:42", token, 3600)             -- with TTL
let v be redis_get("session:42")
redis_set("cfg", json_encode({"theme": "dark"})) -- structured data is explicit

Redis db-index gotcha: redis://host:6379 → scope redis://host (no /0); …/0 is a different scope.