SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0e44b845418998e992d0d8605ac4a45ef3e5c938a72c588423985a8b39589a69' 
  AND token = '43VhieS1QfAxiYkC5iG/YeiuA5/pWV8Qk1nKQmSmHzA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00010

JSON explain

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