# `BIT_AND`

**Applies to:** ✅ Data 360 SQL ✅ Tableau Hyper API

Computes the bitwise `AND` of all non-null input values.

## Syntax

```sql
bit_and(<expression>)
```

## Arguments

### Required

- `<expression>`: An expression of an integral type.

## Returns

Returns the same type as the argument. Returns NULL if no non-null input values exist.

## Considerations

- NULL values are ignored in the calculation.
- Returns NULL when all input values are NULL or the set is empty.
- Useful for checking if specific bits are set across all values.

## Examples

### Bitwise `AND` of Values

Compute the bitwise `AND` of a column.

```sql
SELECT bit_and(flags) AS common_flags
FROM permissions;
```

### Check Common Bits

Find bits that are set in all rows.

```sql
SELECT bit_and(status_code) AS common_status_bits
FROM system_logs
WHERE event_type = 'error';
```

## Related Documentation

- [BIT_OR](/docs/data/data-cloud-query-guide/references/dc-sql-reference/bit-or.md)
- [Aggregate Functions](/docs/data/data-cloud-query-guide/references/dc-sql-reference/aggregate.md)