In the current manual, Table 9.10 <https://www.postgresql.org/docs/13/functions-string.html#FUNCTIONS-STRING-OTHER> has this to say about quote_ident():
> Returns the given string suitably quoted to be used as an identifier in an SQL statement string. Quotes are added only if necessary (i.e., if the string contains non-identifier characters or would be case-folded). Embedded quotes are properly doubled. See also Example 42.1 <https://www.postgresql.org/docs/13/plpgsql-statements.html#PLPGSQL-QUOTE-LITERAL-EXAMPLE> . No mention of SQL key words which are also double-quoted. There was a related question on stackoverflow today: https://stackoverflow.com/questions/66662580/quote-ident-does-not-add-quotes-to-column-name-first I suggest to at least mention key words: * Returns the given string suitably quoted to be used as an identifier in an SQL statement string. Quotes are added only if necessary (i.e., if the string contains non-identifier characters, would be case-folded, or is a reserved key word). *Embedded quotes are properly doubled. See also Example 42.1 <https://www.postgresql.org/docs/13/plpgsql-statements.html#PLPGSQL-QUOTE-LITERAL-EXAMPLE> . To be precise: key words marked *"reserved"* or *"(cannot be function or type)"* in the column "PostgreSQL" of the *SQL Key Words* <https://www.postgresql.org/docs/current/sql-keywords-appendix.html#KEYWORDS-TABLE> table are quoted. And if the GUC quote_all_identifiers <https://www.postgresql.org/docs/current/runtime-config-compatible.html#GUC-QUOTE-ALL-IDENTIFIERS> is set, then all strings are quoted. If that's not too much information, we might make it: *Returns the given string suitably quoted to be used as an identifier in an SQL statement string. Quotes are added only if necessary: if the string contains non-identifier characters, would be case-folded, or is a reserved word (marked "reserved" or "(cannot be function or type)" in Table C.1 <https://www.postgresql.org/docs/current/sql-keywords-appendix.html#KEYWORDS-TABLE>). Embedded quotes are properly doubled. See also Example 42.1 <https://www.postgresql.org/docs/13/plpgsql-statements.html#PLPGSQL-QUOTE-LITERAL-EXAMPLE> and quote_all_identifiers <https://www.postgresql.org/docs/current/runtime-config-compatible.html#GUC-QUOTE-ALL-IDENTIFIERS>.* Regards Erwin
