Menjalankan skrip sql dengan saling ketergantungan

Anda dapat menulis kueri rekursif sederhana yang dimulai dengan semua tampilan yang tidak bergantung pada orang lain dan secara rekursif menambahkan tampilan yang bergantung padanya. Kemudian keluarkan definisi tampilan untuk tampilan ini dalam urutan yang benar, dan Anda telah mendapatkan skrip Anda:

WITH RECURSIVE viewids AS (
   /* all views that don't depend on other views */
   SELECT t.oid, 1 as level
   FROM pg_class t
      JOIN pg_rewrite AS r ON r.ev_class = t.oid
   WHERE r.rulename = '_RETURN'
     AND t.relkind = 'v'
     AND t.relnamespace NOT IN ('pg_catalog'::regnamespace,
                                'information_schema'::regnamespace,
                                'pg_toast'::regnamespace)
     AND NOT EXISTS (
            /* depends on a view */
            SELECT 1
            FROM pg_depend AS d
               JOIN pg_class AS t2 ON d.refobjid = t2.oid
            WHERE d.objid = r.oid
              AND d.classid = 'pg_rewrite'::regclass
              AND d.refclassid = 'pg_class'::regclass
              AND d.deptype = 'n'
              AND d.refobjsubid <> 0
              AND t2.relkind = 'v'
         )
     AND NOT EXISTS (
            /* depends on an extension */
            SELECT 1
            FROM pg_depend
            WHERE objid = t.oid
              AND classid = 'pg_class'::regclass
              AND refclassid = 'pg_extension'::regclass
              AND deptype = 'e'
         )
UNION ALL
   /* all views that depend on these views */
   SELECT t.oid, viewids.level + 1
   FROM pg_class AS t
      JOIN pg_rewrite AS r ON r.ev_class = t.oid
      JOIN pg_depend AS d ON d.objid = r.oid
      JOIN viewids ON viewids.oid = d.refobjid
   WHERE t.relkind = 'v'
     AND r.rulename = '_RETURN'
     AND d.classid = 'pg_rewrite'::regclass                            
     AND d.refclassid = 'pg_class'::regclass
     AND d.deptype = 'n'
     AND d.refobjsubid <> 0
)
/* order the views by level, eliminating duplicates */
SELECT format('CREATE VIEW %s AS%s',
              oid::regclass,
              pg_get_viewdef(oid::regclass))
FROM viewids
GROUP BY oid
ORDER BY max(level);