diff --git a/application/migrations/163_dxcc_index.php b/application/migrations/163_dxcc_index.php
index f847b5ae..792ed61e 100644
--- a/application/migrations/163_dxcc_index.php
+++ b/application/migrations/163_dxcc_index.php
@@ -5,8 +5,21 @@ defined('BASEPATH') OR exit('No direct script access allowed');
 class Migration_dxcc_index extends CI_Migration {
 
 	public function up() {
-		$this->db->query("ALTER TABLE `dxcc_prefixes` ADD INDEX `idx_dxcc_prefixes_logic` (`call`, `start`, `end`)");
-		$this->db->query("ALTER TABLE `dxcc_exceptions` ADD INDEX `idx_dxcc_exceptions_logic` (`call`, `start`, `end`)");
+
+		// check if index idx_dxcc_prefixes_logic exists 
+		// if not, add it
+		$prefixes_index = $this->db->query("SHOW INDEX FROM dxcc_prefixes WHERE Key_name = 'idx_dxcc_prefixes_logic'")->num_rows();
+		if ($prefixes_index == 0) {
+			$this->db->query("ALTER TABLE `dxcc_prefixes` ADD INDEX `idx_dxcc_prefixes_logic` (`call`, `start`, `end`)");
+		}
+
+
+		// check if index dxcc_exceptions exists 
+		// if not, add it
+		$exceptions_index = $this->db->query("SHOW INDEX FROM dxcc_exceptions WHERE Key_name = 'idx_dxcc_exceptions_logic'")->num_rows();
+		if ($exceptions_index == 0) {
+			$this->db->query("ALTER TABLE `dxcc_exceptions` ADD INDEX `idx_dxcc_exceptions_logic` (`call`, `start`, `end`)");
+		}
 	}
 
 	public function down(){