TO_OCT

Convert an integer to its octal (base-8) string representation.

Category: numericReturns: STRINGDialect: PostgreSql

Syntax

TO_OCT(n)

Description

## Overview Returns the octal (base-8) string representation of the given integer. TO_OCT is the historical companion to TO_BIN and TO_HEX and is most commonly used for Unix-style permission masks and compact representation of groups of three bits. ## Behavior - Accepts INTEGER or BIGINT input. - Returns a STRING without leading zeros and without a base prefix. - Returns NULL if the argument is NULL. - TO_OCT(0) returns the string '0'. - Negative values are represented in two's complement at the full width of the input type. ## Numeric precision - TO_OCT is exact: every bit of the input is preserved in the output, grouped into digits of three bits. - The length of the output is variable (ceil((log2(|n|) + 1) / 3) for positive n, full width for negative n). ## Compatibility - Matches the PostgreSQL TO_OCT function. - Complementary to TO_BIN and to engine-specific TO_HEX or HEX functions.

Parameters

Name	Type	Description
`n`		Specifies the integer value to convert. Accepts INTEGER or BIGINT types. Negative values are represented using two's complement notation with the full width of the input type.

Examples

-- Octal of 8
SELECT TO_OCT(8);  -- '10'

-- Octal of 0
SELECT TO_OCT(0);  -- '0'

-- Octal of 255
SELECT TO_OCT(255);  -- '377'

-- Octal of 64
SELECT TO_OCT(64);  -- '100'

-- Octal of 511
SELECT TO_OCT(511);  -- '777'

-- NULL propagation
SELECT TO_OCT(NULL);  -- NULL

Pitfalls

TO_OCT of a negative integer represents the value in two's complement at the input type's full width. TO_OCT(-1) on a BIGINT returns a 22-character string, not '-1'.
Output has no leading zeros. For fixed-width presentation of permission masks, use LPAD(TO_OCT(n), 4, '0') to get a four-digit octal.
TO_OCT does not accept DECIMAL or DOUBLE inputs. Cast to INT explicitly when needed.
The octal base is rarely useful outside of Unix permission masks. Consider TO_BIN for bit-level inspection and TO_HEX (if available) for compact large-value representation.
TO_OCT is not the inverse of octal literals like 0o17 used in some programming languages. SQL typically does not accept those literals natively.