example: add relations to reference-erc20

examples/reference-erc20/ponder.schema.ts

@@ -6,17 +6,10 @@ export const account = onchainTable("account", (t) => ({
   isOwner: t.boolean().notNull(),
 }));
 
-export const allowance = onchainTable(
-  "allowance",
-  (t) => ({
-    owner: t.hex(),
-    spender: t.hex(),
-    amount: t.bigint().notNull(),
-  }),
-  (table) => ({
-    pk: primaryKey({ columns: [table.owner, table.spender] }),
-  }),
-);
+export const accountRelations = relations(account, ({ many }) => ({
+  transferFromEvents: many(transferEvent, { relationName: "from_account" }),
+  transferToEvents: many(transferEvent, { relationName: "to_account" }),
+}));
 
 export const transferEvent = onchainTable(
   "transfer_event",
@@ -34,11 +27,29 @@ export const transferEvent = onchainTable(
 
 export const transferEventRelations = relations(transferEvent, ({ one }) => ({
   fromAccount: one(account, {
+    relationName: "from_account",
     fields: [transferEvent.from],
     references: [account.address],
   }),
+  toAccount: one(account, {
+    relationName: "to_account",
+    fields: [transferEvent.to],
+    references: [account.address],
+  }),
 }));
 
+export const allowance = onchainTable(
+  "allowance",
+  (t) => ({
+    owner: t.hex(),
+    spender: t.hex(),
+    amount: t.bigint().notNull(),
+  }),
+  (table) => ({
+    pk: primaryKey({ columns: [table.owner, table.spender] }),
+  }),
+);
+
 export const approvalEvent = onchainTable("approval_event", (t) => ({
   id: t.text().primaryKey(),
   amount: t.bigint().notNull(),