SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8abbf69225a2acec3950c69080e3296c7449cecaadaa88245d98bfe3c00bcfe5' 
  AND token = 'TsRljU9sbp1jAuf0ToZmybS+cRDzDXK1Zq9BSb7GzRk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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