---
title: "sinh"
slug: "dev-database-reference-sql-functions-numeric-sinh"
updated: 2026-10-30T18:18:51Z
published: 2026-10-30T18:18:51Z
canonical: "docs.vastdata.com/dev-database-reference-sql-functions-numeric-sinh"
---

> ## 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.

# sinh

*Applies to VAST Cluster 5.5.*

*[Functions](/develop/docs/dev-database-reference-sql-functions-index) › [Numeric and math functions](/develop/docs/dev-database-reference-sql-functions-numeric) › Hyperbolic functions.* Returns the hyperbolic sine of a number, `(exp(x) - exp(-x)) / 2`. It takes any number. A result too large for a `DOUBLE` is infinity, not an error.

## Syntax

```
sinh(x)
```

| Argument | Type | Description |
| --- | --- | --- |
| `x` | Any number (`DOUBLE`, `REAL`, an integer or a `DECIMAL`) | Any value, including `inf` and `-inf`. |

**Returns:** `DOUBLE`.

## 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_numeric_sinh`. 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 six readings. Row 3 has no value, and row 6 is too large for its hyperbolic sine to fit in a `DOUBLE`:

```
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_numeric_sinh"'

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}.readings"
run(f"CREATE SCHEMA IF NOT EXISTS {SCHEMA}")
run(f"CREATE TABLE IF NOT EXISTS {TABLE} (id BIGINT, x DOUBLE)")
run(f"INSERT INTO {TABLE} VALUES "
    "(1, 1.0), (2, -1.0), (3, NULL), (4, 0.0), (5, 2.5), (6, 800.0)")
```

```
[]
[]
[(6,)]
```

## What it does

`sinh(x)` is the hyperbolic sine, `(exp(x) - exp(-x)) / 2`. It's an odd function (`sinh(-x)` is `-sinh(x)`), it's 0 at 0, and it grows like `exp(x) / 2` for large `x`. Its inverse is [asinh](/develop/docs/dev-database-reference-sql-functions-numeric-asinh).

| Call | Result |
| --- | --- |
| `sinh(0)` | `0.0` |
| `sinh(1)` | `1.1752011936438014` |
| `sinh(-1)` | `-1.1752011936438014` |
| `sinh(710)` | `1.1169973830808557e+308` |
| `sinh(711)` | `inf`: too large for a `DOUBLE` |
| `sinh(-711)` | `-inf` |

The result is a `DOUBLE` for every numeric argument type: an integer, a `REAL`, a `DECIMAL` or a `DOUBLE`.

```
run("SELECT sinh(0), sinh(1), sinh(-1), sinh(710), sinh(711), sinh(-711)")
run("SELECT typeof(sinh(1::INTEGER)), typeof(sinh(0.5::FLOAT)), typeof(sinh(0.5))")
```

```
[(0.0, 1.1752011936438014, -1.1752011936438014, 1.1169973830808557e+308, inf, -inf)]
[('DOUBLE', 'DOUBLE', 'DOUBLE')]
```

## NULLs and edge cases

| Input | Result |
| --- | --- |
| `NULL` | `NULL` |
| `&apos;inf&apos;::DOUBLE` | `inf` |
| `&apos;-inf&apos;::DOUBLE` | `-inf` |
| `&apos;nan&apos;::DOUBLE` | `nan` |
| `-0.0::DOUBLE` | `-0.0`: the sign of zero is kept |
| The smallest positive `DOUBLE` (`5e-324`) | `5e-324` |
| `&apos;12&apos;` (a string literal holding a number) | Converted to `DOUBLE`: `81377.39570642984` |
| `&apos;abc&apos;` (a string that isn't a number) | Error: `Could not convert string &apos;abc&apos; to DOUBLE` |
| A `BLOB`, date, boolean, list or interval | Error: `No function matches the given name and argument types`, for example `&apos;sinh(DATE)&apos;` |

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

```
run("SELECT sinh(NULL), sinh('inf'::DOUBLE), sinh('-inf'::DOUBLE), sinh('nan'::DOUBLE)")
run("SELECT sinh(-0.0::DOUBLE), sinh(5e-324::DOUBLE), sinh('12')")
run("SELECT sinh('abc')")
run("SELECT sinh(DATE '2026-10-16')")
```

```
[(None, inf, -inf, nan)]
[(-0.0, 5e-324, 81377.39570642984)]
OSError: Could not convert string 'abc' to DOUBLE
InternalError: Binder Error: No function matches the given name and argument types 'sinh(DATE)'. You might need to add explicit type casts.
```

## Examples

The hyperbolic sine of each reading. Row 6 overflows to `inf`, and the query still returns every row:

```
run(f"SELECT id, x, sinh(x) FROM {TABLE} ORDER BY id LIMIT 10")
```

```
[(1, 1.0, 1.1752011936438014), (2, -1.0, -1.1752011936438014), (3, None, None), (4, 0.0, 0.0), (5, 2.5, 6.0502044810397875), (6, 800.0, inf)]
```

Keep only the rows whose hyperbolic sine is above 10:

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

```
[(6, 800.0)]
```

## 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 a function of a column, so `sinh()` is always computed by the Query Engine:

- **In the `SELECT` list,** the scan reads the column and the Query Engine computes `sinh()` for each row it returns.
- **In `WHERE`,** the scan sends the column for every row, and a `FILTER` step in the Query Engine computes `sinh()` 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 sinh(x) > 10")
```

```
┌───────────────────────────┐
│         PROJECTION        │
│    ────────────────────   │
│             #1            │
│                           │
└─────────────┬─────────────┘
┌─────────────┴─────────────┐
│           FILTER          │
│    ────────────────────   │
│      (sinh(x) > 10.0)     │
│                           │
└─────────────┬─────────────┘
┌─────────────┴─────────────┐
│         VAST_SCAN         │
│    ────────────────────   │
│    Function: VAST_SCAN    │
│                           │
│        Projections:       │
│             x             │
│             id            │
│                           │
└───────────────────────────┘
```

## Make it faster

- **Compare the raw column with the inverse of the constant.** `sinh()` grows as its argument grows, so `sinh(x) &gt; 10` is the same condition as `x &gt; asinh(10)`. A function on constants is computed once, before the scan, so the second form is a comparison of the column with a constant, which is pushed down to VAST DataBase. Its plan has no `FILTER` step:

```
plan(f"SELECT id FROM {TABLE} WHERE x > asinh(10)")
run(f"SELECT id, x FROM {TABLE} WHERE x > asinh(10) ORDER BY id LIMIT 10")
```

```
┌───────────────────────────┐
│         VAST_SCAN         │
│    ────────────────────   │
│    Function: VAST_SCAN    │
│      Projections: id      │
│                           │
└───────────────────────────┘
[(6, 800.0)]
```

- **Store the result if you filter on it often.** Compute it when you write the rows and keep it in its own column: a condition on that column is pushed down, a condition on `sinh()` isn't.

## Limitations and errors

- **Overflow gives infinity, not an error.** Above about 710 the result is `inf` (`sinh(711)` is `inf`), and below about -710 it is `-inf`. To find those rows, test the result with [isinf](/develop/docs/dev-database-reference-sql-functions-numeric-isinf):

```
run(f"SELECT id, x, isinf(sinh(x)) FROM {TABLE} ORDER BY id LIMIT 10")
```

```
[(1, 1.0, False), (2, -1.0, False), (3, None, None), (4, 0.0, False), (5, 2.5, False), (6, 800.0, True)]
```

- **Numbers only.** A `BLOB`, a date, a boolean, a list or an interval fails with `No function matches the given name and argument types`; the error lists the one form `sinh` has, `sinh(DOUBLE) -&gt; DOUBLE`. A string literal is converted to `DOUBLE` if it holds a number, and otherwise fails with `Could not convert string &apos;abc&apos; to DOUBLE`.
- **Use `sinh()` rather than the `exp()` formula for large values.** `exp(710)` is already `inf`, so `(exp(x) - exp(-x)) / 2` overflows sooner than `sinh(710)`, which is `1.1169973830808557e+308`.
- **One argument.** `sinh(1, 2)` fails with `No function matches the given name and argument types &apos;sinh(INTEGER_LITERAL, INTEGER_LITERAL)&apos;`.

## Similar functions

| Function | Returns | Result for `1` |
| --- | --- | --- |
| `sinh(x)` | the hyperbolic sine | `1.1752011936438014` |
| [cosh](/develop/docs/dev-database-reference-sql-functions-numeric-cosh) | the hyperbolic cosine, `(exp(x) + exp(-x)) / 2` | `1.5430806348152437` |
| [tanh](/develop/docs/dev-database-reference-sql-functions-numeric-tanh) | the hyperbolic tangent, `sinh(x) / cosh(x)` | `0.7615941559557649` |
| [asinh](/develop/docs/dev-database-reference-sql-functions-numeric-asinh) | the inverse of `sinh` | `asinh(sinh(1))` is `1.0` |
| [exp](/develop/docs/dev-database-reference-sql-functions-numeric-exp) | e to the power `x`; `(exp(x) - exp(-x)) / 2` is the same as `sinh(x)` | `(exp(1) - exp(-1)) / 2` is `1.1752011936438014` |
| [sin](/develop/docs/dev-database-reference-sql-functions-numeric-sin) | the sine of an angle in radians |  |

```
run("SELECT sinh(1), cosh(1), tanh(1), asinh(sinh(1)), (exp(1) - exp(-1)) / 2, sin(1)")
```

```
[(1.1752011936438014, 1.5430806348152437, 0.7615941559557649, 1.0, 1.1752011936438014, 0.8414709848078965)]
```

Clean up:

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

```
[]
[]
```

## See also

- [Numeric and math functions](/develop/docs/dev-database-reference-sql-functions-numeric): all the numeric functions.
- [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.