PostgreSQL permits SELECT FROM ... with no target expressions. It produces rows with zero output columns. See the PostgreSQL SELECT documentation.

JSQLParser fails to parse this syntax when the SELECT is used as a derived table.

SQL Example

SELECT count(*)
FROM (
    SELECT
    FROM (VALUES
        (1, 'alpha'),
        (2, 'beta'),
        (3, 'gamma')
    ) AS t(id, label)
) AS q;

This query executes successfully in PostgreSQL and returns: 3

Parsing error

JSQLParser throws:

ParseException: Encountered: <OPENING_BRACKET> / "(", at line 2, column 6, in lexical state DEFAULT.
Was expecting this terminal within expansion starting at n/a:
    <K_LATERAL> (inside 8769:9) ...

The reported ( begins the derived table. The PostgreSQL syntax JSQLParser needs to handle is the inner SELECT immediately followed by FROM, with no target expressions.

Tested with JSQLParser 5.4-SNAPSHOT.