Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3e7d909bcac38778537a9f424f3354dbc927e3217be2e37f89ae6ee2e0fb64bc' 
  AND token = '5L9u1iAeypo/U4ylIa2n3XkNSPf6hFfdynqUFAqRNyk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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