---
title: ">> (shift right)"
slug: "dev-database-reference-sql-functions-operators-shift-right"
updated: 2026-10-30T18:18:56Z
published: 2026-10-30T18:18:56Z
canonical: "docs.vastdata.com/dev-database-reference-sql-functions-operators-shift-right"
---

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

# >> (shift right)

*Applies to VAST Cluster 5.5.*

*[Functions](/develop/docs/dev-database-reference-sql-functions-index) › [Operators and predicates](/develop/docs/dev-database-reference-sql-functions-operators-and-predicates) › Bitwise operators.* `a >> n` shifts the bits of `a` right by `n` places, which divides `a` by 2 to the power `n` and rounds down: `256 >> 4` is `16`. A negative number keeps its sign, and a shift past the width of the type gives `0`.

## Syntax

```
a >> n
```

| Argument | Type | Description |
| --- | --- | --- |
| `a` | An integer type (`TINYINT` to `HUGEINT`, signed or unsigned), or `BIT` | The value to shift. |
| `n` | An integer | How many places to shift. |

**Returns:** the integer type of the arguments: `256 >> 4` is an `INTEGER`. For a `BIT` value, a `BIT`.

## Set up the examples

The examples connect with the ADBC driver, as in [VAST Query Engine (ADBC)](/develop/docs/dev-database-integrations-adbc), and work in a schema called `docs_sql_fn_operators_shift_right`. Set `QE_ENDPOINT`, `AWS_ACCESS_KEY_ID`, `AWS_SECRET_ACCESS_KEY` and `VASTDB_BUCKET` ([SQL reference](/develop/docs/dev-database-reference-sql-index#example-connect-and-use-a-transaction)), and run the blocks in order in one Python session. Below each block is the output you should see.

This block connects, defines the `run()` and `plan()` helpers, and creates a table of four values `n`, each with a number of places `k` to shift it by. The last row has no values:

```
import os
import re

import adbc_driver_manager
import adbc_driver_manager.dbapi as dbapi
import adbc_driver_vastdb

BUCKET = os.environ["VASTDB_BUCKET"]
SCHEMA = f'"{BUCKET}/docs_sql_fn_operators_shift_right"'

conn = dbapi.connect(
    driver=adbc_driver_vastdb.get_driver_path(),
    db_kwargs={
        "vast.db.endpoint": os.environ["QE_ENDPOINT"],
        "vast.db.access_key": os.environ["AWS_ACCESS_KEY_ID"],
        "vast.db.secret_key": os.environ["AWS_SECRET_ACCESS_KEY"],
    },
    autocommit=True,
)

def server_message(e):
    """The server's message in a driver error, without the request ID or the echoed statement."""
    text = re.sub(r"\[req=0x[0-9a-f]+\]: ", "", str(e))
    found = (re.search(r'message: "(.*?)", request_id', text, re.S)
             or re.search(r"description: (.*)\)", text, re.S))
    message = found.group(1) if found else text.strip().splitlines()[-1]
    message = re.sub(r"^Plan query: '.*?' failed with: ", "", message, flags=re.S)
    message = re.split(r"\\n|\n", message)[0].replace('\\"', '"')
    return message.replace(BUCKET, "<bucket>")

def run(sql):
    """Run one statement. Print the rows it returns, or the error."""
    try:
        with conn.cursor() as cur:
            cur.execute(sql)
            rows = cur.fetchall() if cur.description else []
    except (adbc_driver_manager.Error, OSError) as e:
        print(f"{type(e).__name__}: {server_message(e)}")
    else:
        print(rows)

def plan(sql):
    """Print the plan without its ~N Rows lines: the table's row count, which can still be 0 just after an insert."""
    with conn.cursor() as cur:
        cur.execute("EXPLAIN " + sql)
        steps = cur.fetchall()[0][1]
    print("\n".join(line for line in steps.splitlines() if "Rows" not in line))

TABLE = f"{SCHEMA}.shifts"
run(f"CREATE SCHEMA IF NOT EXISTS {SCHEMA}")
run(f"CREATE TABLE IF NOT EXISTS {TABLE} (id BIGINT, n INTEGER, k INTEGER)")
run(f"INSERT INTO {TABLE} VALUES (1, 256, 4), (2, -16, 2), (3, 100000, 7), (4, NULL, NULL)")
```

```
[]
[]
[(4,)]
```

## What it does

`a &gt;&gt; n` moves every bit of `a` down by `n` places and drops the bits that fall off the end, so the result is `a` divided by 2 to the power `n`, rounded down: `100 &gt;&gt; 3` is `12`.

- **Negative numbers keep their sign.** The places at the top are filled with copies of the sign bit, so `-16 &gt;&gt; 2` is `-4` and `-1 &gt;&gt; 10` stays `-1`. Rounding down means towards minus infinity: `-100 &gt;&gt; 3` is `-13`, where `-100 // 8` is `-12`.
- **A shift past the width gives `0`.** `256 &gt;&gt; 40` on an `INTEGER` is `0`, and so is `-1 &gt;&gt; 63`; the largest value of a type shifted by its width in bits is `0` too. A negative `n` gives `0` too: `256 &gt;&gt; -1` is `0`. None of these is an error.
- **Unsigned types fill with zeros:** `255::UTINYINT &gt;&gt; 1` is `127`.

## NULLs and edge cases

| Input | Result |
| --- | --- |
| `256 &gt;&gt; 4`, `256 &gt;&gt; 8`, `256 &gt;&gt; 9`, `256 &gt;&gt; 0` | `16`, `1`, `0`, `256` |
| `256 &gt;&gt; 40` (past the 32 bits of an `INTEGER`) | `0` |
| `-16 &gt;&gt; 2`, `-1 &gt;&gt; 10`, `-1 &gt;&gt; 63` | `-4`, `-1`, `0` |
| `256 &gt;&gt; -1` | `0` |
| `(-128)::TINYINT &gt;&gt; 1`, `255::UTINYINT &gt;&gt; 1` | `-64`, `127` |
| `9223372036854775807 &gt;&gt; 62`, `1::HUGEINT &gt;&gt; 200` | `1`, `0` |
| `NULL &gt;&gt; 1`, `1 &gt;&gt; NULL` | `NULL` |
| `1.5 &gt;&gt; 1` (a `DECIMAL`) | Error: `No function matches the given name and argument types &apos;&gt;&gt;(DECIMAL(2,1), INTEGER_LITERAL)&apos;` |
| `&apos;abc&apos; &gt;&gt; k` (a string) | Error: `Could not choose a best candidate function for the function call &quot;&gt;&gt;(STRING_LITERAL, INTEGER)&quot;` |

The same cases, as the cluster returns them. They use the table and helpers from [Set up the examples](/develop/docs/dev-database-reference-sql-functions-operators-shift-right#set-up-the-examples):

```
run("SELECT 256 >> 4, 256 >> 8, 256 >> 9, 256 >> 0, 256 >> 40")
run("SELECT -16 >> 2, -1 >> 10, -1 >> 63, 256 >> -1")
run("SELECT (-128)::TINYINT >> 1, 255::UTINYINT >> 1, 9223372036854775807 >> 62, 1::HUGEINT >> 200")
run("SELECT NULL >> 1, 1 >> NULL")
run("SELECT 1.5 >> 1")
run(f"SELECT 'abc' >> k FROM {TABLE} LIMIT 1")
```

```
[(16, 1, 0, 256, 0)]
[(-4, -1, 0, 0)]
[(-64, 127, 1, Decimal('0'))]
[(None, None)]
InternalError: Binder Error: No function matches the given name and argument types '>>(DECIMAL(2,1), INTEGER_LITERAL)'. You might need to add explicit type casts.
InternalError: Binder Error: Could not choose a best candidate function for the function call ">>(STRING_LITERAL, INTEGER)". In order to select one, please add explicit type casts.
```

## Examples

Shift each value by its own number of places. `-16` keeps its sign:

```
run(f"SELECT id, n, k, n >> k FROM {TABLE} ORDER BY id LIMIT 10")
```

```
[(1, 256, 4, 16), (2, -16, 2, -4), (3, 100000, 7, 781), (4, None, None, None)]
```

Take the high part of each value: `n &gt;&gt; 4` drops the lowest 4 bits. Keep the rows where it's larger than 10:

```
run(f"SELECT id, n >> 4 FROM {TABLE} ORDER BY id LIMIT 10")
run(f"SELECT id FROM {TABLE} WHERE (n >> 4) > 10 ORDER BY id LIMIT 10")
```

```
[(1, 16), (2, -1), (3, 6250), (4, None)]
[(1,), (3,)]
```

## How it runs in VAST

The Query Engine runs on the cluster's CNodes, and a query on a table starts with a scan in VAST DataBase (`VAST_SCAN`). VAST DataBase can evaluate a comparison of a column with a constant, but not an operation on a column, so `&gt;&gt;` on a column is always computed by the Query Engine:

- **In the `SELECT` list,** the scan reads the columns and the Query Engine computes `&gt;&gt;` for each row it returns.
- **In `WHERE`,** the scan sends the columns for every row, and a `FILTER` step in the Query Engine computes `&gt;&gt;` and keeps the rows that match. No rows are skipped in storage.

The plan of the `WHERE` example shows the `FILTER` step above the scan:

```
plan(f"SELECT id FROM {TABLE} WHERE (n >> 4) > 10")
```

```
┌───────────────────────────┐
│         PROJECTION        │
│    ────────────────────   │
│             #1            │
│                           │
└─────────────┬─────────────┘
┌─────────────┴─────────────┐
│           FILTER          │
│    ────────────────────   │
│      ((n >> 4) > 10)      │
│                           │
└─────────────┬─────────────┘
┌─────────────┴─────────────┐
│         VAST_SCAN         │
│    ────────────────────   │
│    Function: VAST_SCAN    │
│                           │
│        Projections:       │
│             n             │
│             id            │
│                           │
└───────────────────────────┘
```

## Make it faster

- **Rewrite a shifted comparison as a range on the column.** `(n &gt;&gt; 10) = 1` holds for exactly the values from 1024 up to, not including, 2048, so `n &gt;= 1024 AND n &lt; 2048` gives the same rows. That range is a comparison of the raw column with constants, which is pushed down to VAST DataBase, so rows that don't match never leave storage. Its plan has no `FILTER` step:

```
plan(f"SELECT id FROM {TABLE} WHERE n >= 1024 AND n < 2048")
```

```
┌───────────────────────────┐
│         VAST_SCAN         │
│    ────────────────────   │
│    Function: VAST_SCAN    │
│      Projections: id      │
│                           │
└───────────────────────────┘
```

- **Store the part you filter on.** If you often filter on the high bits of a value, keep them in their own column when you write the rows.

## Limitations and errors

- **Integers and `BIT` only.** A `DECIMAL`, `DOUBLE`, `FLOAT`, `BOOLEAN`, `DATE`, `INTERVAL`, `BLOB` or list fails with `No function matches the given name and argument types`. A string literal fails with `Could not choose a best candidate function`, because it could be a `BIT` or an integer; cast it.
- **Rounds towards minus infinity.** For a negative `a`, `a &gt;&gt; n` and `a // 2^n` can differ by 1. Use [//](/develop/docs/dev-database-reference-sql-functions-operators-integer-division) to round towards zero.
- **A shift past the width isn't an error.** It gives `0`, for negative values too, and so does a negative `n`. Check `n` yourself if a shift that large means bad data.

```
run("SELECT -100 >> 3, -100 // 8, CAST('12' AS INTEGER) >> 1")
```

```
[(-13, -12, 6)]
```

## Similar functions

| Operator or function | What it does | Result for `100` and `3` | Result for `-100` and `3` |
| --- | --- | --- | --- |
| `a &gt;&gt; n` | shifts right by `n` bits; rounds towards minus infinity | `12` | `-13` |
| [//](/develop/docs/dev-database-reference-sql-functions-operators-integer-division) `(a // 8)` | divides and drops the fraction; rounds towards zero | `12` | `-12` |
| [<<](/develop/docs/dev-database-reference-sql-functions-operators-shift-left) | shifts left by `n` bits | `800` | error: negative `a` |

```
run("SELECT 100 >> 3, -100 >> 3, 100 // 8, -100 // 8, 100 << 3")
run("SELECT -100 << 3")
```

```
[(12, -13, 12, -12, 800)]
OSError: Cannot left-shift negative number -100
```

Clean up:

```
run(f"DROP TABLE IF EXISTS {TABLE}")
run(f"DROP SCHEMA IF EXISTS {SCHEMA}")
conn.close()
```

```
[]
[]
```

## See also

- [Operators and predicates](/develop/docs/dev-database-reference-sql-functions-operators-and-predicates): all the operators.
- [<< (shift left)](/develop/docs/dev-database-reference-sql-functions-operators-shift-left), [& (bitwise AND)](/develop/docs/dev-database-reference-sql-functions-operators-bitwise-and).
- [Where filters run](/develop/docs/dev-database-reference-sql-select#where-filters-run) and [pushdowns](/develop/docs/dev-database-reference-pushdowns).
- [EXPLAIN](/develop/docs/dev-database-reference-sql-explain): how to read a plan.