Are database reads inside queries cached globally?

export const listCreatedShifts = query({
  args: {  },
  handler: async (ctx, args) => {
    const commentMap: Record<Id<"post">, any[]> = {}
    for (let i = 0; i < posts.length; i++) {
      const post = posts[i]
      const comments = await ctx.db
        .query("comments")
        .withIndex("by_post", (q) => q.eq("post", post._id))
        .collect()
      commentMap[posts._id] = comments
    }
    return { posts, comments }
  },
})

export const getPost = query({
  args: { post: v.id("post") },
  handler: async (ctx, args) => {
    const post = await ctx.db.get(args.postId)
    if (!post) {
      throw new ConvexError("Post not found")
    }
    const comments = await ctx.db
      .query("comments")
      .withIndex("by_post", (q) => q.eq("post", post._id))
      .collect()