SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5a5178161b164d5c9d497a8bff655d816cb88663fe42267ba68e913c092a620f' 
  AND token = 'kRY60PoXA6tIIQzh/V3vMlMIS3MWkxKX5XCQ8CHK+3w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

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