SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9749c53bdef2c458770dd7a47d8f0b029cc1a42c51d0ff2324a54801ac18ef6e' 
  AND token = 'bkP/sEjFBK7yw15UAT767qjiZzRGtUOkDTqvC6J0HEo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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