> ## Documentation Index
> Fetch the complete documentation index at: https://docs.allium.so/llms.txt
> Use this file to discover all available pages before exploring further.

# Blocks

Blocks are the building blocks of blockchains and rollups. A block contains transactions which contains instructions which will alter the state of the solana blockchain incrementally. Transactions within a block can only be executed one after the other, not in parallel. Instructions within a transaction can only be executed one after the other, not in parallel.

Learn more in the official Solana documentation [here](https://docs.solana.com/developing/programming-model/accounts).

### Table Columns

<table><thead><tr><th>Column Name</th><th>Description</th><th>Type</th><th width="198">Example</th><th data-hidden>Column Name</th></tr></thead><tbody><tr><td>slot</td><td>The time of the slot and also block. Within the time window of a slot a block may or may not be proposed and voted upon. Only non-empty slots are indexed.</td><td>number</td><td>276304227</td><td /></tr><tr><td>height</td><td>The number of <a href="https://docs.solana.com/terminology#block">blocks</a> beneath the current block. The first block after the <a href="https://docs.solana.com/terminology#genesis-block">genesis block</a> has height one. height \< slot as some each slot as at most 1 block.<br />blocks \< 81032053 have no block height</td><td>number</td><td>255661589</td><td /></tr><tr><td>timestamp</td><td>The time when the slot was included on the blockchain.<br />blocks \< 39824214 have no block timestamp</td><td>timestamp\_ntz</td><td>2024-07-08 02:16:54.000</td><td /></tr><tr><td>hash</td><td>Unique identifier for that slot. (base58)</td><td>varchar</td><td>36KR3aiVEZYSJDb8wgWBWpXbYykuz3BJagFRMhFijKxA</td><td /></tr><tr><td>parent\_slot</td><td>Slot number of the non-empty slot preceding this slot</td><td>number</td><td>276304226</td><td><h3>Table Columns</h3><table><thead><tr><th>Column Name</th><th>Description</th><th>Sample Value</th><th data-hidden>Column Name</th></tr></thead><tbody><tr><td>block\_timestamp</td><td>The time when the block was included on the blockchain.</td><td><code>2022-09-15 13:51:47</code></td><td /></tr><tr><td>block\_number</td><td>The length of the chain, in blocks.</td><td><code>15539508</code></td><td /></tr><tr><td>block\_hash</td><td>Unique identifier for that block.</td><td><code>0x25680259dfb40b4ee724ae22fda01a34e6d598c5f2fc25b6d871cb56c488de70</code></td><td /></tr><tr><td>parent\_hash</td><td>Unique identifier of the block preceding this block, also known as the parent block.</td><td><code>0x46707e33e9dca09ec95f0fc8b996e3bbce3ad3e02ea270939207bab1f809066f</code></td><td><h3>Table Columns</h3><table><thead><tr><th>Column Name</th><th>Description</th><th>Sample Value</th><th data-hidden>Column Name</th></tr></thead><tbody><tr><td>block\_timestamp</td><td>The time when the block was included on the blockchain.</td><td><code>2022-09-15 13:51:47</code></td><td /></tr><tr><td>block\_number</td><td>The length of the chain, in blocks.</td><td><code>15539508</code></td><td /></tr><tr><td>block\_hash</td><td>Unique identifier for that block.</td><td><code>0x25680259dfb40b4ee724ae22fda01a34e6d598c5f2fc25b6d871cb56c488de70</code></td><td /></tr><tr><td>parent\_hash</td><td>Unique identifier of the block preceding this block, also known as the parent block.</td><td><code>0x46707e33e9dca09ec95f0fc8b996e3bbce3ad3e02ea270939207bab1f809066f</code></td><td /></tr><tr><td>gas\_limit</td><td>Gas limit of the current block.</td><td><code>30000000</code></td><td /></tr><tr><td>gas\_used</td><td>Total gas used in the block.</td><td><code>6999860</code></td><td /></tr><tr><td>miner</td><td><strong>Proof of Stake</strong><br />Address receiving fees from transactions in this block<br /><br /><strong>Proof of Work</strong><br />Address of the miner that mined this block.</td><td><code>0x388c818ca8b9251b393131c08a736a67ccb19297</code></td><td /></tr><tr><td>transaction\_count</td><td>Number of transactions included in this block.</td><td><code>95</code></td><td /></tr><tr><td>nonce</td><td><strong>Proof of Stake</strong><br />Unused post Merge. The value will always be <code>0x0000000000000000</code><br /><br /><strong>Proof of Work</strong><br />Used to demonstrate proof of work during mining</td><td><code>0x090c1db284e8b101</code></td><td /></tr><tr><td>difficulty</td><td>The effort required to mine this block.<br /><br /><strong>Proof of Stake</strong><br />Always <code>0</code></td><td><code>11594723311525902</code></td><td /></tr><tr><td>total\_difficulty</td><td>Total difficulty of the chain until this block.</td><td><code>58750003716598352816469</code></td><td /></tr><tr><td>size</td><td>The size of the block, in bytes, as determined by the <code>gas\_limit</code>.</td><td><code>23628</code></td><td /></tr><tr><td>base\_fee\_per\_gas</td><td>Post London Upgrade (<a href="https://eips.ethereum.org/EIPS/eip-1559">EIP1559</a>), this represents the minimum <code>gas\_used</code>  required for a transaction to be included in a block.<br /><br />Represented in <a href="https://www.investopedia.com/terms/w/wei.asp">wei</a>.</td><td><code>10966453825</code></td><td /></tr></tbody></table></td></tr><tr><td>gas\_limit</td><td>Gas limit of the current block.</td><td><code>30000000</code></td><td /></tr><tr><td>gas\_used</td><td>Total gas used in the block.</td><td><code>6999860</code></td><td /></tr><tr><td>miner</td><td><strong>Proof of Stake</strong><br />Address receiving fees from transactions in this block<br /><br /><strong>Proof of Work</strong><br />Address of the miner that mined this block.</td><td><code>0x388c818ca8b9251b393131c08a736a67ccb19297</code></td><td /></tr><tr><td>transaction\_count</td><td>Number of transactions included in this block.</td><td><code>95</code></td><td /></tr><tr><td>nonce</td><td><strong>Proof of Stake</strong><br />Unused post Merge. The value will always be <code>0x0000000000000000</code><br /><br /><strong>Proof of Work</strong><br />Used to demonstrate proof of work during mining</td><td><code>0x090c1db284e8b101</code></td><td /></tr><tr><td>difficulty</td><td>The effort required to mine this block.<br /><br /><strong>Proof of Stake</strong><br />Always <code>0</code></td><td><code>11594723311525902</code></td><td /></tr><tr><td>total\_difficulty</td><td>Total difficulty of the chain until this block.</td><td><code>58750003716598352816469</code></td><td /></tr><tr><td>size</td><td>The size of the block, in bytes, as determined by the <code>gas\_limit</code>.</td><td><code>23628</code></td><td /></tr><tr><td>base\_fee\_per\_gas</td><td>Post London Upgrade (<a href="https://eips.ethereum.org/EIPS/eip-1559">EIP1559</a>), this represents the minimum <code>gas\_used</code>  required for a transaction to be included in a block.<br /><br />Represented in <a href="https://www.investopedia.com/terms/w/wei.asp">wei</a>.</td><td><code>10966453825</code></td><td /></tr></tbody></table></td></tr><tr><td>previous\_block\_hash</td><td>Unique identifier of the non-empty slot preceding this slot</td><td>varchar</td><td>2ymHtgWXKxVf5BVVdt34onGrkUm7oDCHTMBBzkJt1rsV</td><td /></tr><tr><td>transaction\_count</td><td>Number of transactions in the block</td><td>number</td><td>875</td><td /></tr><tr><td>nonvoting\_transaction\_count</td><td>Number of nonvoting transactions in the block</td><td>number</td><td>441</td><td /></tr><tr><td>reward\_count</td><td>Number of rewards in the block</td><td>number</td><td>1</td><td /></tr></tbody></table>