Improve postgres management scripts

site-cookbooks/kosmos_postgresql/files/list_subscriptions.sh

@@ -1,5 +1,16 @@
 #!/bin/bash
-for db in $(psql -Atqc "SELECT datname FROM pg_database WHERE datallowconn AND datname NOT IN ('template1','postgres')"); do
-  echo "==== DB: $db ===="
-  psql -d "$db" -c "SELECT * FROM pg_stat_subscription;"
+set -euo pipefail
+
+psql -Atqc "
+SELECT datname
+FROM pg_database
+WHERE datallowconn
+  AND datname NOT IN ('template1','postgres')
+" | while read -r db; do
+  result=$(psql -X -At -d "$db" -c "SELECT * FROM pg_stat_subscription;" 2>/dev/null || true)
+
+  if [[ -n "$result" ]]; then
+    echo "==== DB: $db ===="
+    echo "$result"
+  fi
 done