Help with deciding when to use indexes.

// missing imports from drizzle to avoid discord character limit
import { teamsTable } from "./clubSchemas";
import crypto from "node:crypto";

const v4ID = (name: string) =>
  varchar(name, { length: 36 }).$defaultFn(() => crypto.randomUUID());

export const usersTable = mysqlTable("users", {
  id: v4ID("id").primaryKey(),
  email: varchar("email", { length: 255 }).notNull(),
  name: text("name").notNull(),
  teamId: text("team_id").notNull(),
  createdAt: timestamp("created_at").defaultNow().notNull(),
  lastEdited: timestamp("last_edited").defaultNow().notNull(),
});

export const usersRelations = relations(usersTable, ({ many, one }) => ({
  posts: many(postsTable),
  team: one(teamsTable, {
    fields: [usersTable.teamId],
    references: [teamsTable.id],
  }),
}));

export const postsTable = mysqlTable("posts", {
  id: v4ID("id").primaryKey(),
  authorId: text("author_id").notNull(),
  content: text("content").notNull(),
  debateId: text("debate_id").notNull(),
  createdAt: timestamp("created_at").defaultNow().notNull(),
  likeCount: mediumint("like_count").default(0).notNull(),
  dislikeCount: mediumint("dislike_count").default(0).notNull(),
});

export const postsRelations = relations(postsTable, ({ one, many }) => ({
  author: one(usersTable, {
    fields: [postsTable.authorId],
    references: [usersTable.id],
  }),
  debate: one(debatesTable, {
    fields: [postsTable.debateId],
    references: [debatesTable.id],
  }),
}));

export const debatesTable = mysqlTable("debates", {
  id: v4ID("id").notNull(),
  name: varchar("name", { length: 255 }).primaryKey(),
  teamId: text("team_id"),
  debateType: mysqlEnum("debate_type", ["league", "team"]).notNull(),
});

export const debatesRelations = relations(debatesTable, ({ one, many }) => ({
  posts: many(
  team: one(teamsTable, {
    fields: [debatesTable.teamId],
    references: [teamsTable.id],
  }),
}));