SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6e69fe6f75d9dd7cd8367c68c8b5a25786947570ee4006ac44192da656ffa417' 
  AND token = '/GACVkYr9ojJPqdoHw06v3Bq3vXwpFDpgonrPgPTeUY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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