SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f397c93edd8078016c3eb4bea1a51e7763c9a1772d866bbf14064a9a6305a23e' 
  AND token = 'R9Fgacq38baVqLaW1cYSoRpT2WFREwfshEzPMqKPjok=' 
  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"
    }
  }
}