SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bd3fe50ca5dda881f22af8fd9fccc41f855654cf95660adec789e4da72cf9146' 
  AND token = 'uDJ+k17/G83T7WSgPO82/95woolfykOIGjE2ANHq+GE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00050

JSON explain

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