SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3a4dfe0b12062971fa54e2beeb61f428f8a924bbc18ddef465270002d5fbf5a1' 
  AND token = 'k0yeAPR/1uSvJct+zRJbpzSV+EaEOsr3ylpEAJMO++s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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