> ## Documentation Index
> Fetch the complete documentation index at: https://mintlify-poc.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# approximate_row_count()

> Estimate the number of rows in a table

export const HYPERTABLE = 'hypertable';

export const PG = 'Postgres';

<Icon icon="tag" iconType="duotone" /> Since [0.10.0][tsdb-0.10.0]

Get approximate row count for {HYPERTABLE}, distributed {HYPERTABLE}, or regular {PG} table based on catalog estimates.
This function supports tables with nested inheritance and declarative partitioning.

The accuracy of `approximate_row_count` depends on the database having up-to-date statistics about the table or
{HYPERTABLE}, which are updated by `VACUUM`, `ANALYZE`, and a few DDL commands. If you have auto-vacuum configured on
your table or {HYPERTABLE}, or changes to the table are relatively infrequent, you might not need to explicitly
`ANALYZE` your table as shown below. Otherwise, if your table statistics are too out-of-date, running this command
updates your statistics and yields more accurate approximation results.

## Samples

Get the approximate row count for a single {HYPERTABLE}.

```sql theme={"dark"}
ANALYZE conditions;

SELECT * FROM approximate_row_count('conditions');
```

The expected output:

```
approximate_row_count
---------------------
               240000
```

## Arguments

The syntax is:

```sql theme={"dark"}
SELECT approximate_row_count('<table_name>');
```

| Name       | Type     | Default | Required | Description                                              |
| ---------- | -------- | ------- | -------- | -------------------------------------------------------- |
| `relation` | REGCLASS | -       | ✔        | {HYPERTABLE} or regular {PG} table to get row count for. |

## Returns

| Column                  | Type   | Description                                                                      |
| ----------------------- | ------ | -------------------------------------------------------------------------------- |
| `approximate_row_count` | BIGINT | A numeric estimate of the number of rows in the specified table or {HYPERTABLE}. |

[tsdb-0.10.0]: https://github.com/timescale/timescaledb/releases/tag/0.10.0