observation_fact scalar function

Example

Runs locally

-- Label an address in stored execution evidence
SELECT observation_fact(
  '0x2000000000000000000000000000000000000002'::ADDRESS,
  'writer'::VARCHAR
) IS NOT NULL AS declared;
-- => [{"declared":"true"}]

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API reference

observation_fact(ADDRESS, VARCHAR) #

Declares a human-readable label for an address without scheduling a READ.

Inputs

Name	Type	Use
`address`	ADDRESS Address associated with the label in stored execution evidence.	required positional
`label`	VARCHAR Text containing 1-256 valid UTF-8 bytes and no NUL byte; validated by this constructor.	required positional

Returns

Name	Type
`observation`	OBSERVATION

Address-label OBSERVATION. Returns an address fact. If an observation list declares the same address repeatedly, the last declaration is effective and earlier declarations remain stored as ineffective.

Guidance

No state read

Address facts do not count as expanded observation points and do not execute EVM code.