SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0d2fbd66211d57ca610e82c7aecddd85a4d5670f81111f2ff8a3a72aa1ad3ee9' 
  AND token = 'MssRl2i90rohJzRzg0MKg3dGf65HK+OqOhsN5bQjtmg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}