LiteralSetValue

Represents a single column assignment (one entry of the SQL SET clause).

Field	Type	Description
concreteType	STRING	Required. Full name of the exact type used.
columnName	STRING	Target column name to update.
value	OBJECT	Literal JSON value to assign to the field in each target document: string, number, boolean, object, array, or null. Omit the "value" property to remove/unset the field (`undefined`); include `"value": null` to store JSON null. Must be a literal constant — no SQL or expressions; value is bound and stored as-is.