document retainBody for glob() loader

src/content/docs/en/reference/content-loader-reference.mdx

@@ -28,7 +28,7 @@ Astro provides two built-in loaders to help you fetch your collections. Both off
 
 The `glob()` loader creates entries from directories of files from anywhere on the filesystem. The supported file types are Markdown, MDX, Markdoc, JSON, YAML, and TOML files.
 
-This loader accepts an object with the following properties: `pattern`, `base` (optional), and `generateId` (optional).
+This loader accepts an object with the following properties: `pattern`, `base` (optional), `generateId` (optional), and `retainBody (optional)`.
 
 ```ts title="src/content.config.ts" {2,6,11,17-21}
 import { defineCollection } from 'astro:content';
@@ -44,6 +44,16 @@ const blog = defineCollection({
   loader: glob({ pattern: "**/*.(md|mdx)", base: "./src/data/blog" }),
   schema: /* ... */
 });
+const posts = defineCollection({
+  /* Retrieve all Markdown files in your blog directory and prevent
+   * the raw body of content files from being stored in the data store. */
+  loader: glob({
+    pattern: '**/*.md',
+    base: './src/content/blog',
+    retainBody: false
+  }),
+  schema: /* ... */
+});
 const authors = defineCollection({
   /* Retrieve all JSON files in your authors directory while retaining
    * uppercase letters in the ID. */
@@ -91,6 +101,25 @@ A callback function that returns a unique string per entry in a collection. It a
 
 By default it uses [`github-slugger`](https://github.com/Flet/github-slugger) to generate a slug with [kebab-cased](https://developer.mozilla.org/en-US/docs/Glossary/Kebab_case) words.
 
+#### `retainBody`
+
+<p>
+
+**Type:** `boolean`<br />
+**Default:** `true`
+<Since v="5.17.0" />
+</p>
+
+Whether or not to store the raw body of content files in the data store.
+
+When `retainBody` is `false`, [`entry.body`](/en/reference/modules/astro-content/#body) will be `undefined` instead of containing the raw file contents.
+
+Setting this property to `false` significantly reduces the deployed size of the data store and helps avoid hitting size limits for sites with very large collections.
+
+For Markdown files, the rendered body will still be available in the `entry.rendered.html` property, and the `entry.filePath` property will still point to the original file. 
+
+For MDX collections, this will dramatically reduce the size of the collection, as there will no longer be any body retained in the store.
+
 ### `file()` loader
 
 <p>

src/content/docs/en/reference/modules/astro-content.mdx

@@ -274,10 +274,12 @@ An object of frontmatter properties inferred from your collection schema ([see `
 
 #### `body`
 
-**Type:** `string`
+**Type:** `string | undefined`
 
 A string containing the raw, uncompiled body of the Markdown or MDX document.
 
+Note that if [`retainBody`](/en/reference/content-loader-reference/#retainbody) is set to `false`, this value will be `undefined` instead of containing the raw file contents.
+
 ### `CollectionKey`
 
 <p><Since v="3.1.0" /></p>