fix Model findById data loader (#3657)

Co-authored-by: Tim <hello@timsmart.co>

.changeset/real-pumas-tease.md

@@ -0,0 +1,6 @@
+---
+"@effect/sql-mysql2": patch
+"@effect/sql": patch
+---
+
+fix Model findById data loader

packages/sql-mysql2/test/Model.test.ts

@@ -1,7 +1,7 @@
 import { Schema } from "@effect/schema"
 import { Model, SqlClient } from "@effect/sql"
 import { assert, describe, it } from "@effect/vitest"
-import { Effect } from "effect"
+import { Effect, Option } from "effect"
 import { MysqlContainer } from "./utils.js"
 
 class User extends Model.Class<User>("User")({
@@ -67,6 +67,31 @@ describe("Model", () => {
       Effect.catchTag("ContainerError", () => Effect.void)
     ), { timeout: 60_000 })
 
+  it.scopedLive("findById data loader", () =>
+    Effect.gen(function*() {
+      const repo = yield* Model.makeDataLoaders(User, {
+        tableName: "users",
+        idColumn: "id",
+        spanPrefix: "UserRepository",
+        window: 10
+      })
+      const sql = yield* SqlClient.SqlClient
+      yield* sql`CREATE TABLE users (id INT AUTO_INCREMENT PRIMARY KEY, name VARCHAR(255), age INT)`
+      const alice = yield* repo.insert(User.insert.make({ name: "Alice", age: 30 }))
+      const john = yield* repo.insert(User.insert.make({ name: "John", age: 30 }))
+
+      const [alice2, john2] = yield* Effect.all([
+        repo.findById(alice.id),
+        repo.findById(john.id)
+      ], { batching: true })
+
+      assert.deepStrictEqual(Option.map(alice2, (alice) => alice.name), Option.some("Alice"))
+      assert.deepStrictEqual(Option.map(john2, (john) => john.name), Option.some("John"))
+    }).pipe(
+      Effect.provide(MysqlContainer.ClientLive),
+      Effect.catchTag("ContainerError", () => Effect.void)
+    ), { timeout: 60_000 })
+
   it.effect("update returns result", () =>
     Effect.gen(function*() {
       const repo = yield* Model.makeRepository(User, {

packages/sql/src/Model.ts

@@ -848,13 +848,10 @@ select * from ${sql(options.tableName)} where ${sql(idColumn)} = LAST_INSERT_ID(
         })
       ) as any
 
-    const findByIdResolver = yield* SqlResolver.grouped(`${options.spanPrefix}/findById`, {
-      Request: idSchema,
-      RequestGroupKey(id) {
-        return id
-      },
+    const findByIdResolver = yield* SqlResolver.findById(`${options.spanPrefix}/findById`, {
+      Id: idSchema,
       Result: Model,
-      ResultGroupKey(request) {
+      ResultId(request) {
         return request[idColumn]
       },
       execute: (ids) => sql`select * from ${sql(options.tableName)} where ${sql.in(idColumn, ids)}`