SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5b3e43ed5bfa346160d5f3adc6aaaa0080329f22c679589d11bb74f414e05f5b' 
  AND token = 'iFsyiyUpqURCLknAAHpx9xfvXo27FQoE393tzH5FG5k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}