src/Database/Schema/RedshiftSchema.php
public function addForeignKey($name, $table, $columns, $refTable, $refColumns, $delete = null, $update = null)
    {
        // ON DELETE and ON UPDATE not supported by Redshift
        return parent::addForeignKey($name, $table, $columns, $refTable, $refColumns, null, null);
    }
public function addForeignKey($name, $table, $columns, $refTable, $refColumns, $delete = null, $update = null)
    {
        // ON DELETE and ON UPDATE not supported by Redshift
        return parent::addForeignKey($name, $table, $columns, $refTable, $refColumns, null, null);
    }
{@InheritDoc}