Initial commit using sqlc for query generation.

Basic crud ops and join queries to use sqlc, more complex either from
scratch or with a query builder later.

sql/queries.sql

@@ -0,0 +1,25 @@
+-- name: GetUser :one
+SELECT * FROM users
+WHERE id = $1 LIMIT 1;
+
+-- name: ListUsers :many
+SELECT * FROM users
+ORDER BY name;
+
+-- name: CreateUser :one
+INSERT INTO users (
+  name, age
+) VALUES (
+  $1, $2
+)
+RETURNING *;
+
+-- name: UpdateUser :exec
+UPDATE users
+  set name = $2,
+  age = $3
+WHERE id = $1;
+
+-- name: DeleteUser :exec
+DELETE FROM users
+WHERE id = $1;

sql/schema.sql

@@ -0,0 +1,6 @@
+CREATE TABLE users (
+  id   BIGSERIAL PRIMARY KEY,
+  name text      NOT NULL,
+  age  int       NOT NULL
+);
+

sqlc.yml

@@ -0,0 +1,15 @@
+version: "2"
+sql:
+  - engine: "postgresql"
+    queries: "sql/queries.sql"
+    schema: "sql/schema.sql"
+    gen:
+      go:
+        # 'db' is a standard package name for database logic
+        package: "db"
+        out: "internal/db"
+        sql_package: "pgx/v5"
+        # Recommended for better Go code:
+        emit_json_tags: true
+        emit_interface: true
+        emit_exact_table_names: false