diff --git a/lib/dml/pgsql_native_moodle_database.php b/lib/dml/pgsql_native_moodle_database.php
index f5d569080ca..c54384e7cbb 100644
--- a/lib/dml/pgsql_native_moodle_database.php
+++ b/lib/dml/pgsql_native_moodle_database.php
@@ -410,7 +410,8 @@ class pgsql_native_moodle_database extends moodle_database {
 
         $tablename = $this->prefix.$table;
 
-        $sql = "SELECT a.attnum, a.attname AS field, t.typname AS type, a.attlen, a.atttypmod, a.attnotnull, a.atthasdef, d.adsrc
+        $sql = "SELECT a.attnum, a.attname AS field, t.typname AS type, a.attlen, a.atttypmod, a.attnotnull, a.atthasdef,
+                       CASE WHEN a.atthasdef THEN pg_catalog.pg_get_expr(d.adbin, d.adrelid) END AS adsrc
                   FROM pg_catalog.pg_class c
                   JOIN pg_catalog.pg_namespace as ns ON ns.oid = c.relnamespace
                   JOIN pg_catalog.pg_attribute a ON a.attrelid = c.oid