make select optional on a query (#148)

Author: samwillis

.changeset/lemon-deer-tell.md

@@ -0,0 +1,5 @@
+---
+"@tanstack/db": patch
+---
+
+the select operator is not optional on a query, it will default to returning the whole row for a basic query, and a namespaced object when there are joins

packages/db/src/query/pipeline-compiler.ts

@@ -6,7 +6,11 @@ import { processOrderBy } from "./order-by.js"
 import { processSelect } from "./select.js"
 import type { Query } from "./schema.js"
 import type { IStreamBuilder } from "@electric-sql/d2ts"
-import type { KeyedStream, NamespacedAndKeyedStream } from "../types.js"
+import type {
+  InputRow,
+  KeyedStream,
+  NamespacedAndKeyedStream,
+} from "../types.js"
 
 /**
  * Compiles a query into a D2 pipeline
@@ -136,7 +140,10 @@ export function compileQueryPipeline<T extends IStreamBuilder<unknown>>(
   // Process the SELECT clause - this is where we flatten the structure
   const resultPipeline: KeyedStream | NamespacedAndKeyedStream = query.select
     ? processSelect(pipeline, query, mainTableAlias, allInputs)
-    : pipeline
-
+    : !query.join && !query.groupBy
+      ? pipeline.pipe(
+          map(([key, row]) => [key, row[mainTableAlias]] as InputRow)
+        )
+      : pipeline
   return resultPipeline as T
 }

packages/db/src/query/query-builder.ts

@@ -438,6 +438,7 @@ export class BaseQueryBuilder<TContext extends Context<Schema>> {
               Input
           >
         }
+        hasJoin: true
       }
     >
   >
@@ -474,6 +475,7 @@ export class BaseQueryBuilder<TContext extends Context<Schema>> {
         schema: TContext[`schema`] & {
           [K in T]: RemoveIndexSignature<TContext[`baseSchema`][T]>
         }
+        hasJoin: true
       }
     >
   >
@@ -513,6 +515,7 @@ export class BaseQueryBuilder<TContext extends Context<Schema>> {
         schema: TContext[`schema`] & {
           [K in TAs]: RemoveIndexSignature<TContext[`baseSchema`][TFrom]>
         }
+        hasJoin: true
       }
     >
   >
@@ -864,10 +867,12 @@ export function queryBuilder<TBaseSchema extends Schema = {}>() {
 
 export type ResultsFromContext<TContext extends Context<Schema>> = Flatten<
   TContext[`result`] extends object
-    ? TContext[`result`]
-    : TContext[`result`] extends undefined
-      ? TContext[`schema`]
-      : object
+    ? TContext[`result`] // If there is a select we will have a result type
+    : TContext[`hasJoin`] extends true
+      ? TContext[`schema`] // If there is a join, the query returns the namespaced schema
+      : TContext[`default`] extends keyof TContext[`schema`]
+        ? TContext[`schema`][TContext[`default`]] // If there is no join we return the flat default schema
+        : never // Should never happen
 >
 
 export type ResultFromQueryBuilder<TQueryBuilder> = Flatten<

packages/db/src/query/types.ts

@@ -20,6 +20,7 @@ export type Context<
   schema: TSchema
   default?: keyof TSchema
   result?: Record<string, unknown>
+  hasJoin?: boolean
 }
 
 // Helper types