[Migration] Check if indexes already exist before trying to add them

application/migrations/163_dxcc_index.php

@@ -5,9 +5,22 @@ defined('BASEPATH') OR exit('No direct script access allowed');
 class Migration_dxcc_index extends CI_Migration {
 
 	public function up() {
+
+		// 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(){
 		$this->db->query("ALTER TABLE dxcc_prefixes DROP INDEX idx_dxcc_prefixes_logic");