change index of new tables to unique index

db/migrate.py

@@ -19,6 +19,7 @@ async def migrate(self):
         migrations: list[tuple[int, Callable[[psycopg.AsyncConnection[DictRow], Redis[str]], Awaitable[None]]]] = [
             (1, self.migrate_1_add_block_validator_index),
             (2, self.migrate_2_add_address_tag_and_validator_table),
+            (3, self.migrate_3_change_tag_validator_index_to_unique),
         ]
         async with self.pool.connection() as conn:
             async with conn.cursor() as cur:
@@ -63,4 +64,14 @@ async def migrate_2_add_address_tag_and_validator_table(conn: psycopg.AsyncConne
     website text,
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 )""")
-        await conn.execute("create index validator_info_address_index on validator_info (address)")
+        await conn.execute("create index validator_info_address_index on validator_info (address)")
+
+    @staticmethod
+    async def migrate_3_change_tag_validator_index_to_unique(conn: psycopg.AsyncConnection[DictRow], redis: Redis[str]):
+        await conn.execute("drop index address_tag_address_index")
+        await conn.execute("drop index address_tag_tag_index")
+        await conn.execute("create unique index address_tag_address_index on address_tag (address)")
+        await conn.execute("create unique index address_tag_tag_index on address_tag (tag)")
+
+        await conn.execute("drop index validator_info_address_index")
+        await conn.execute("create unique index validator_info_address_index on validator_info (address)")