The following documentation comment has been logged on the website: Page: https://www.postgresql.org/docs/15/functions-comparisons.html Description:
In section #FUNCTIONS-COMPARISONS-IN-SCALAR operator IN is described as a expression for scalars, and as a shorthand notation for a combination of operators || and = In section #COMPOSITE-TYPE-COMPARISON described extension, to use operators with a records, like "record operator record" for uncertain set of operators, and noted "Composite type comparisons are allowed when the operator is =, <>, <, <=, > or >=, or has semantics similar to one of these." and with a some difficult to understand note about B-trees. And as result, I can't see a direct description for allowance to use a syntax like a "(key_part_1, key_part_2) IN ( ('B',1), ('C',2) )" So I propose to mention record types in section #FUNCTIONS-COMPARISONS-IN-SCALAR. Phrase "The right-hand side is a parenthesized list of scalar expressions." can be replaced to phrases "The right-hand side is a parenthesized list of scalar or record expressions. About records [see further](#COMPOSITE-TYPE-COMPARISON)" Also I propose make similar adjustments in other sections of this page, and make cross-links here and in a https://www.postgresql.org/docs/current/functions-subquery.html page near the text mentions of each others.