ngds/console/migrations/m261009_000002_allow_empty_declaration_payer.php

<?php

use yii\db\Migration;

class m261009_000002_allow_empty_declaration_payer extends Migration
{
    public function safeUp()
    {
        $this->setPayerNullability(false);
    }

    public function safeDown()
    {
        $table = '{{%APPROACH_DEC_ORDER}}';
        $nullCount = (int) (new \yii\db\Query())
            ->from($table)
            ->where(['USER_ID' => null])
            ->count('*', $this->db);
        if ($nullCount > 0) {
            throw new \RuntimeException('Cannot restore APPROACH_DEC_ORDER.USER_ID NOT NULL while guest declaration rows exist.');
        }

        $this->setPayerNullability(true);
    }

    private function setPayerNullability(bool $notNull): void
    {
        $table = '{{%APPROACH_DEC_ORDER}}';
        $schema = $this->db->getTableSchema($table, true);
        if (!$schema || !isset($schema->columns['USER_ID'])) {
            throw new \RuntimeException('APPROACH_DEC_ORDER.USER_ID column was not found.');
        }

        $column = $schema->columns['USER_ID'];
        if ((bool) $column->allowNull === !$notNull) {
            return;
        }

        $definition = $this->db->getSchema()->createColumnSchemaBuilder($column->type, $column->size);
        $definition->notNull($notNull);
        $this->alterColumn($table, 'USER_ID', $definition);
    }
}