ClickHouse/docs/en/sql_reference/functions/bit_functions.md

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---
toc_priority: 48
toc_title: Bit
---
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# Bit functions {#bit-functions}
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Bit functions work for any pair of types from UInt8, UInt16, UInt32, UInt64, Int8, Int16, Int32, Int64, Float32, or Float64.
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The result type is an integer with bits equal to the maximum bits of its arguments. If at least one of the arguments is signed, the result is a signed number. If an argument is a floating-point number, it is cast to Int64.
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## bitAnd(a, b) {#bitanda-b}
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## bitOr(a, b) {#bitora-b}
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## bitXor(a, b) {#bitxora-b}
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## bitNot(a) {#bitnota}
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## bitShiftLeft(a, b) {#bitshiftlefta-b}
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## bitShiftRight(a, b) {#bitshiftrighta-b}
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## bitRotateLeft(a, b) {#bitrotatelefta-b}
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## bitRotateRight(a, b) {#bitrotaterighta-b}
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## bitTest {#bittest}
Takes any integer and converts it into [binary form](https://en.wikipedia.org/wiki/Binary_number), returns the value of a bit at specified position. The countdown starts from 0 from the right to the left.
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**Syntax**
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``` sql
SELECT bitTest(number, index)
```
**Parameters**
- `number` integer number.
- `index` position of bit.
**Returned values**
Returns a value of bit at specified position.
Type: `UInt8`.
**Example**
For example, the number 43 in base-2 (binary) numeral system is 101011.
Query:
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``` sql
SELECT bitTest(43, 1)
```
Result:
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``` text
┌─bitTest(43, 1)─┐
│ 1 │
└────────────────┘
```
Another example:
Query:
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``` sql
SELECT bitTest(43, 2)
```
Result:
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``` text
┌─bitTest(43, 2)─┐
│ 0 │
└────────────────┘
```
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## bitTestAll {#bittestall}
Returns result of [logical conjuction](https://en.wikipedia.org/wiki/Logical_conjunction) (AND operator) of all bits at given positions. The countdown starts from 0 from the right to the left.
The conjuction for bitwise operations:
0 AND 0 = 0
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0 AND 1 = 0
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1 AND 0 = 0
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1 AND 1 = 1
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**Syntax**
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``` sql
SELECT bitTestAll(number, index1, index2, index3, index4, ...)
```
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**Parameters**
- `number` integer number.
- `index1`, `index2`, `index3`, `index4` positions of bit. For example, for set of positions (`index1`, `index2`, `index3`, `index4`) is true if and only if all of its positions are true (`index1` ⋀ `index2`, ⋀ `index3``index4`).
**Returned values**
Returns result of logical conjuction.
Type: `UInt8`.
**Example**
For example, the number 43 in base-2 (binary) numeral system is 101011.
Query:
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``` sql
SELECT bitTestAll(43, 0, 1, 3, 5)
```
Result:
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``` text
┌─bitTestAll(43, 0, 1, 3, 5)─┐
│ 1 │
└────────────────────────────┘
```
Another example:
Query:
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``` sql
SELECT bitTestAll(43, 0, 1, 3, 5, 2)
```
Result:
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``` text
┌─bitTestAll(43, 0, 1, 3, 5, 2)─┐
│ 0 │
└───────────────────────────────┘
```
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## bitTestAny {#bittestany}
Returns result of [logical disjunction](https://en.wikipedia.org/wiki/Logical_disjunction) (OR operator) of all bits at given positions. The countdown starts from 0 from the right to the left.
The disjunction for bitwise operations:
0 OR 0 = 0
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0 OR 1 = 1
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1 OR 0 = 1
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1 OR 1 = 1
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**Syntax**
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``` sql
SELECT bitTestAny(number, index1, index2, index3, index4, ...)
```
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**Parameters**
- `number` integer number.
- `index1`, `index2`, `index3`, `index4` positions of bit.
**Returned values**
Returns result of logical disjuction.
Type: `UInt8`.
**Example**
For example, the number 43 in base-2 (binary) numeral system is 101011.
Query:
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``` sql
SELECT bitTestAny(43, 0, 2)
```
Result:
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``` text
┌─bitTestAny(43, 0, 2)─┐
│ 1 │
└──────────────────────┘
```
Another example:
Query:
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``` sql
SELECT bitTestAny(43, 4, 2)
```
Result:
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``` text
┌─bitTestAny(43, 4, 2)─┐
│ 0 │
└──────────────────────┘
```
## bitCount {#bitcount}
Calculates the number of bits set to one in the binary representation of a number.
**Syntax**
```sql
bitCount(x)
```
**Parameters**
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- `x` — [Integer](../../sql_reference/data_types/int_uint.md) or [floating-point](../../sql_reference/data_types/float.md) number. The function uses the value representation in memory. It allows supporting floating-point numbers.
**Returned value**
- Number of bits set to one in the input number.
The function doesn't convert input value to a larger type ([sign extension](https://en.wikipedia.org/wiki/Sign_extension)). So, for example, `bitCount(toUInt8(-1)) = 8`.
Type: `UInt8`.
**Example**
Take for example the number 333. Its binary representation: 0000000101001101.
Query:
```sql
SELECT bitCount(333)
```
Result:
```text
┌─bitCount(333)─┐
│ 5 │
└───────────────┘
```
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[Original article](https://clickhouse.tech/docs/en/query_language/functions/bit_functions/) <!--hide-->