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

# Place Bulk Order

> Place a post-only bulk order on the exchange

The **Bulk Order API** allows a client to submit and manage multiple limit orders
(both bids and asks) in a single atomic transaction. Eac account can have at most one Bulk Order per
market.

This API **cancels all existing resting liquidity** for the market provided and **replaces it with
the new bulk set of orders** (bids and asks). Partial failures (e.g., an order that cannot be posted
due to a `PostOnly` violation) do **not revert the transaction** — that particular order will simply
be skipped or partially placed. Cancelled price levels and sizes will be returned explicitly in the
update event.

\*\* NOTE \*\*

* Bulk Order Placements with a non-increasing `sequence_number` will be rejected.
* Order updates that reduce size will maintain its position in the matching queue, order updates that
  increase size will be moved to the end of the matching queue.

**Function:**

```
{package}::dex_accounts_entry::place_bulk_orders_to_subaccount
```

**ABI Object:**

```typescript theme={null}
const functionAbi: MoveFunction = {
  name: "place_bulk_orders_to_subaccount",
  visibility: "private",
  is_entry: true,
  is_view: false,
  generic_type_params: [],
  params: [
    "&signer",
    "0x1::object::Object<{package}::dex_accounts::Subaccount>",
    "0x1::object::Object<{package}::perp_market::PerpMarket>",
    "u64",
    "vector<u64>",
    "vector<u64>",
    "vector<u64>",
    "vector<u64>",
    "0x1::option::Option<address>",
    "0x1::option::Option<u64>",
  ],
  return: [],
};
```

**Parameters:**

* `signer` - The account signer
* `subaccount` - The Trading Account object
* `market` - The PerpMarket object
* `sequence_number` - The monotonically increasing number associated with this order
* `bid_prices` - `` `vector<u64>` `` - Array of bid prices in chain units
* `bid_sizes` - `` `vector<u64>` `` - Array of bid sizes in chain units
* `ask_prices` - `` `vector<u64>` `` - Array of ask prices in chain units
* `ask_sizes` - `` `vector<u64>` `` - Array of ask sizes in chain units
* `builder_address` - Optional builder address `` `<Option<address>>` ``
* `builder_fees` - Optional builder fee `` `<Option<u64>>` ``

## Time in Force

**Bulk Orders are Post-Only limit orders**.

**Example:**

<CodeGroup>
  ```typescript Typescript theme={null}
  const transaction = await aptos.transaction.build.simple({
    sender: account.accountAddress,
    data: {
      function: `${PACKAGE}::dex_accounts_entry::place_bulk_orders_to_subaccount`,
      typeArguments: [],
      functionArguments: [
        "0x123...abc", // subaccountAddr
        "0x456...def", // marketAddr (PerpMarket object address)
        1, // sequenceNumber (must be monotonically increasing)
        [5670000000, 5680000000, 5690000000], // bidPrices (in chain units)
        [1000000000, 2000000000, 3000000000], // bidSizes (in chain units)
        [5710000000, 5720000000, 5730000000], // askPrices (in chain units)
        [1000000000, 2000000000, 3000000000], // askSizes (in chain units)
        null, // builderAddress (optional)
        null, // builderFees (optional)
      ],
    },
  });
  ```

  ```python Python theme={null}
  transaction = rest_client.build_transaction(
      sender=account.address(),
      payload={
          "function": f"{PACKAGE}::dex_accounts_entry::place_bulk_orders_to_subaccount",
          "type_arguments": [],
          "function_arguments": [
              "0x123...abc",  # subaccountAddr
              "0x456...def",  # marketAddr (PerpMarket object address)
              1,  # sequenceNumber (must be monotonically increasing)
              [5670000000, 5680000000, 5690000000],  # bidPrices (in chain units)
              [1000000000, 2000000000, 3000000000],  # bidSizes (in chain units)
              [5710000000, 5720000000, 5730000000],  # askPrices (in chain units)
              [1000000000, 2000000000, 3000000000],  # askSizes (in chain units)
              None,  # builderAddress (optional)
              None,  # builderFees (optional)
          ],
      },
  )
  ```
</CodeGroup>