cyremur•12mo ago

Index on optional nested properties

Is there a reason that on the schema:

export const vGameState = v.object({
  playerOne: v.optional(
    v.object({ userId: v.id("users"), username: v.string() })
  ),
  playerOneId: v.optional(v.id("users")),
  playerTwo: v.optional(
    v.object({ userId: v.id("users"), username: v.string() })
  ),
  playerTwoId: v.optional(v.id("users")),
});

export const vGameState = v.object({
  playerOne: v.optional(
    v.object({ userId: v.id("users"), username: v.string() })
  ),
  playerOneId: v.optional(v.id("users")),
  playerTwo: v.optional(
    v.object({ userId: v.id("users"), username: v.string() })
  ),
  playerTwoId: v.optional(v.id("users")),
});

with indices

export default defineSchema({
  games: defineTable(vGameState)
    .index("by_player_one", ["playerOneId"])
    .index("by_player_one_nested", ["playerOne.userId"])
    .index("by_player_two", ["playerTwoId"])
    .index("by_player_two_nested", ["playerTwo.userId"]),
});

export default defineSchema({
  games: defineTable(vGameState)
    .index("by_player_one", ["playerOneId"])
    .index("by_player_one_nested", ["playerOne.userId"])
    .index("by_player_two", ["playerTwoId"])
    .index("by_player_two_nested", ["playerTwo.userId"]),
});

I can do

    const games1 = await ctx.db
      .query("games")
      .withIndex("by_player_one", (q) => q.eq("playerOneId", userId))
      .order("desc")
      .collect();

    const games1 = await ctx.db
      .query("games")
      .withIndex("by_player_one", (q) => q.eq("playerOneId", userId))
      .order("desc")
      .collect();

But the nested one gets a type error?

    const games1_nested = await ctx.db
      .query("games")
      .withIndex("by_player_one_nested", (q) =>
        q.eq("playerOne.userId", userId)
      )
      .order("desc")
      .collect();

    const games1_nested = await ctx.db
      .query("games")
      .withIndex("by_player_one_nested", (q) =>
        q.eq("playerOne.userId", userId)
      )
      .order("desc")
      .collect();

4 Replies

deen•12mo ago

It's because the playerOne object is optional in your schema. The error message is confusing. The "undefined" is playerOne when it is missing. You can't read a property from an object that doesn't exist.

sshader•12mo ago

Hmm pretty sure the types are just wrong here -- I'll work on a fix. In the meantime, a type cast to get around it userId as any or a // @ts-expect-error should unblock you (and you can verify you get the results you expect) The mental model I use for indexes is that on every document insertion / change, we look up the values for each field path listed in the index, and essentially create a tuple that we can sort by (the index key). So documents without playerOne will have playerOne.userId as undefined

cyremurOP•12mo ago

Maybe I'm too spoiled by ?. but I expected both variants to resolve to Id<"users"> | undefined

deen•12mo ago

Yeah I thought you were spoiled too, but looks like you were right! Nice one 😁

Index on optional nested properties

Did you find this page helpful?