getTable($this->getTableName())->hasColumn('deduplicate')) { throw new SkipMigration("The deduplicate column has already been added to the {$this->getTableName()} table."); } } public function up(Schema $schema): void { $this->addSql("ALTER TABLE {$this->getTableName()} ADD deduplicate VARCHAR(32) DEFAULT NULL"); $this->addSql("CREATE INDEX deduplicate_date_added ON {$this->getTableName()} (deduplicate, date_added)"); } public function down(Schema $schema): void { $this->addSql("DROP INDEX deduplicate_date_added ON {$this->getTableName()}"); $this->addSql("ALTER TABLE {$this->getTableName()} DROP deduplicate"); } private function getTableName(): string { return $this->prefix.'notifications'; } }