BIT_OR

Return the bitwise OR of two integer values.

Category: miscReturns: INTDialect: PostgreSql

Syntax

BIT_OR(a, b)

Description

## Overview Returns an integer whose bits are the bitwise OR of the corresponding bits in the two operands. A bit in the result is 1 if the bit at the same position is 1 in either input. Use this function to set feature bits, merge permission masks, or union two bitmaps. BIT_OR is the function form of the `|` operator and pairs naturally with BIT_AND and BIT_NOT for flag manipulation in generated SQL and analytics pipelines. ## Behavior - Returns NULL if either argument is NULL. - Operates on the two's complement bit pattern of the integers. - Both arguments are promoted to the widest integer type among the two before the operation. - Result is deterministic and side effect free. - BIT_OR(x, x) equals x. BIT_OR(x, 0) equals x. BIT_OR(x, -1) equals -1 (all bits on). ## Bit semantics - Bits are numbered from 0 at the least significant end. - To set bit n in a value, OR with `1 << n`: `BIT_OR(x, 1 << n)`. - Multiple feature bits can be set in one expression: `BIT_OR(BIT_OR(x, 1), 4)` sets bits 0 and 2. ## Compatibility - Equivalent to the standard `|` operator and to the PG-compat function of the same name.

Parameters

Name	Type	Description
`a`		Specifies the first integer operand. Treated as a two's complement signed value across the full width of the argument type.
`b`		Specifies the second integer operand. Must be the same integer width as the first operand after implicit promotion.

Examples

-- Basic bitwise OR of 12 (1100) and 10 (1010)
SELECT BIT_OR(12, 10);  -- 14

-- OR with zero returns the original value
SELECT BIT_OR(42, 0);  -- 42

-- Combining two flag sets
SELECT BIT_OR(3, 12) AS combined_flags;  -- 15

-- Set a specific feature bit (bit 3) on every account
SELECT account_id, BIT_OR(feature_flags, 8) AS updated_flags
FROM security.catalog.accounts;

-- Merge permission masks across roles in a user-role join
SELECT user_id, BIT_OR(role_mask, extra_mask) AS effective_mask
FROM security.catalog.user_roles;

-- NULL propagation
SELECT BIT_OR(5, NULL);  -- NULL

Pitfalls

Do not confuse BIT_OR (the scalar bitwise function) with the aggregate bit-or function of the same name in some dialects. DeltaForge's BIT_OR is strictly a two-argument scalar operation.
Integer promotion can widen the result. ORing an INT with a BIGINT returns a BIGINT; cast back explicitly if you are writing to a narrower column.
NULL operands propagate. If you want NULL to act like zero (an identity for OR), wrap the argument in COALESCE: `BIT_OR(x, COALESCE(y, 0))`.
Setting a bit that is already set is a no-op and not an error. Rely on this rather than branching with CASE.