[migration-tools] Don't import metadata for zero-length files into CTA Catalogue

migration/oracle_catalogue_castor_migration.sql

@@ -318,18 +318,19 @@ BEGIN
       IF var2ndTapePool IS NOT NULL THEN
         importTapePool(var2ndTapePool, inVO_id);
       END IF;
+      -- import metadata into the CTA catalogue
+      populateCTAFilesFromCASTOR(inEOSCTAInstance, varTapePool, inVO_id);
+      IF inDryRun = 0 THEN
+        CNS_ctaLog(varTapePool, 'CASTOR metadata import completed successfully');
+      ELSE
+        CNS_ctaLog(varTapePool, 'CASTOR metadata import completed successfully [dry-run mode]');
+      END IF;
     ELSE
       -- 0-byte files are special as they do not belong to any tape pool
       CNS_zeroByteFilesForCTAExport(inVO);
       -- extract all directories metadata as above
       CNS_dirsForCTAExport(varTapePool);
-    END IF;
-    -- import metadata into the CTA catalogue
-    populateCTAFilesFromCASTOR(inEOSCTAInstance, varTapePool, inVO_id);
-    IF inDryRun = 0 THEN
-      CNS_ctaLog(varTapePool, 'CASTOR metadata import completed successfully');
-    ELSE
-      CNS_ctaLog(varTapePool, 'CASTOR metadata import completed successfully [dry-run mode]');
+      CNS_ctaLog(varTapePool, 'CASTOR zero-length file metadata imported successfully');
     END IF;
   EXCEPTION WHEN OTHERS THEN
     -- any error is logged and raised to the caller