docs/sql-manual/sql-functions/bitwise-functions/bitshiftleft.md

---
{
"title": "BIT_SHIFT_LEFT",
"language": "en"
}
---

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## bit_shift_left
### description
#### syntax

`BIT_SHIFT_LEFT(BIGINT x, TINYINT c)`

Do logical left shift to `BIGINT` type x by c bits, and return result as a `BIGINT`.
Return zero if `c` is less than 0.

### example
Normal case
```sql
select 8 as x, number as c, bit_shift_left(8, number) as bit_shift_left from numbers("number"="5")
--------------

+------+------+----------------+
| x    | c    | bit_shift_left |
+------+------+----------------+
|    8 |    0 |              8 |
|    8 |    1 |             16 |
|    8 |    2 |             32 |
|    8 |    3 |             64 |
|    8 |    4 |            128 |
+------+------+----------------+
5 rows in set (0.04 sec)
```
Left shift result of `9223372036854775807` which is `BIGINT_MAX` by 1 bit will get -2.
```sql
WITH tbl AS (
  SELECT 9223372036854775807 AS BIGINT_MAX
)
SELECT BIGINT_MAX, bit_shift_left(BIGINT_MAX, 1)
FROM tbl
--------------

+---------------------+-------------------------------+
| BIGINT_MAX          | bit_shift_left(BIGINT_MAX, 1) |
+---------------------+-------------------------------+
| 9223372036854775807 |                            -2 |
+---------------------+-------------------------------+
1 row in set (0.05 sec)
```
### keywords

    BITSHIFT, BITSHIFTLEFT