SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '05beb49f51382230ab753df8cb691dc2005b749d61614cda44adc6f571e72e29' 
  AND token = '/ZgotURVVfUTo690Xchx77uhr4vBnu6xs/qPwJgtrIg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}