Polkadot

Polkadot is a relay chain with a set of system chains beside it, each doing one job the relay chain does not. Every one is its own dataset, queried as <chain_id>.<table>, and all of them carry the same three core tables. The relay chain carries two more.

Chains

Chain	`chain_id`	Since	What it holds
Relay chain	`polkadot`	2020-06	Consensus and the chains connected to it. Issues no tokens and hosts no apps, so the catalog tables built on those hold nothing for it.
Asset Hub	`polkadotassethub`	2021-12	Fungible and non-fungible assets. Its tokens reach the token list.
Bridge Hub	`polkadotbridgehub`	2023-05	Bridges from Polkadot to other networks.
Collectives	`polkadotcollectives`	2022-11	On-chain bodies, including the Technical Fellowship.
Coretime	`polkadotcoretime`	2024-09	Sales of blockspace to the chains that use it.
People	`polkadotpeople`	2024-07	Identities, which moved off the relay chain onto their own.

Every column is documented at Substrate ▸ Overview.

Tables

Every chain above carries blocks, extrinsics and events. The relay chain carries two more.

Table	Chains	Description
`blocks`	All	One row per block, with its author and extrinsic count.
`extrinsics`	All	One row per extrinsic, the Substrate equivalent of a transaction.
`events`	All	One row per event emitted during block execution.
`initialize_finalize_events`	`polkadot`	Events emitted while a block is initialized and finalized.
`chain_ids`	`polkadot`	A mapping of numeric ids to chain identifiers.

Sample queries

The tables split by day on block_timestamp (blocks on timestamp). Bound that column in every query; without a bound the query reads the whole table.

Event-emitting pallets
One system chain
Chain entry lookup

Rank event-emitting pallets on the relay chain on one day.

select
    event_pallet,
    count(*) as events
from `polkadot.events`
where block_timestamp >= timestamp('2026-08-20')
  and block_timestamp < timestamp('2026-08-21')
group by event_pallet
order by events desc
limit 20

Count daily extrinsics on Asset Hub over one week. Swap the dataset name for any other chain in the table above; the shape is the same.

select
    timestamp_trunc(block_timestamp, day) as day,
    count(*) as extrinsics
from `polkadotassethub.extrinsics`
where block_timestamp >= timestamp('2026-08-16')
  and block_timestamp < timestamp('2026-08-23')
group by day
order by day

Look up Polkadot’s chain entry and the project it belongs to.

select
    chains.chain_id,
    chains.name as chain_name,
    projects.name as project_name,
    projects.primary_market_sector
from `dimensions.chains` as chains
join `dimensions.projects` as projects using (project_id)
where chains.chain_id = 'polkadot'

Notes

initialize_finalize_events has the same columns as events and stopped receiving new rows on 2024-07-29. chain_ids is not split by day and carries two columns, id and chain_id. The relay chain issues no tokens and hosts no apps, so the catalog tables built on those things hold nothing for it. Asset Hub is where its tokens live, and those do reach the token list. Chains covers the list of chains and the daily tables built on it. Tokens covers the token list.

Overview

Core entities

Core datasets

Market verticals

Chain verticals

Chains

Tables

Sample queries

Notes

​Chains

​Tables

​Sample queries

​Notes

Chains

Tables

Sample queries

Notes