@@ -14,7 +14,7 @@ class Version20180603135342 extends AbstractMigration
     {
         $currenciesCount = $this->sql('SELECT count(*) FROM currencies')->fetchColumn(0);
         if ($currenciesCount <= 0) {
-            $this->sql('INSERT INTO currencies (id, name, code, exchange_rate) VALUES (1, \'Česká koruna\', \'CZK\', 1)');
+            $this->sql('INSERT INTO currencies (id, name, code, exchange_rate) VALUES (1, \'Euro\', \'EUR\', 1)');
             $this->sql('ALTER SEQUENCE currencies_id_seq RESTART WITH 2');
 
             $defaultCurrencyId = $this->sql('SELECT COUNT(*) FROM setting_values WHERE name = \'defaultCurrencyId\' AND domain_id = 0;')->fetchColumn(0);
<?php

namespace Shopsys\FrameworkBundle\Migrations;

use Doctrine\DBAL\Schema\Schema;
use Shopsys\MigrationBundle\Component\Doctrine\Migrations\AbstractMigration;

class Version20180603135342 extends AbstractMigration
{
    /**
     * @param \Doctrine\DBAL\Schema\Schema $schema
     */
    public function up(Schema $schema)
    {
        $currenciesCount = $this->sql('SELECT count(*) FROM currencies')->fetchColumn(0);
        if ($currenciesCount <= 0) {
            $this->sql('INSERT INTO currencies (id, name, code, exchange_rate) VALUES (1, \'Česká koruna\', \'CZK\', 1)');
            $this->sql('ALTER SEQUENCE currencies_id_seq RESTART WITH 2');

            $defaultCurrencyId = $this->sql('SELECT COUNT(*) FROM setting_values WHERE name = \'defaultCurrencyId\' AND domain_id = 0;')->fetchColumn(0);
            if ($defaultCurrencyId <= 0) {
                $this->sql('INSERT INTO setting_values (name, domain_id, value, type) VALUES (\'defaultCurrencyId\', 0, 1, \'integer\')');
            }

            $defaultDomainCurrencyId = $this->sql('SELECT COUNT(*) FROM setting_values WHERE name = \'defaultDomainCurrencyId\' AND domain_id = 1;')->fetchColumn(0);
            if ($defaultDomainCurrencyId <= 0) {
                $this->sql('INSERT INTO setting_values (name, domain_id, value, type) VALUES (\'defaultDomainCurrencyId\', 1, 1, \'integer\')');
            }
        }
    }

    /**
     * @param \Doctrine\DBAL\Schema\Schema $schema
     */
    public function down(Schema $schema)
    {
    }
}

Changing migrations isn't really safe, a new migration should be generated if necessary.