Several dimensions include _ID, _CODE, and _NAME, such as
AD_UNIT_ID, AD_PLACEMENT_CODE, or PLATFORM_TYPE_NAME. These
all have slightly different meanings and uses, so it's important to be aware of them when selecting
dimensions for your report.
_ID dimensions
Dimensions that end in _ID display a guaranteed unique ID for the value,
within that dimension, which refers to a specific entity in an AdSense account.
If you need to ensure uniqueness in the dimension values, use an _ID dimension.
_CODE dimensions
Dimensions that end in _CODE normally use a unique, language-independent code for
the value. There are, however, some exceptions where the value may only be unique to an account or
ad client, if the value refers to an AdSense account entity.
If you need to do any sort of special handling of dimension values and can’t use an
_ID dimension, use a _CODE dimension.
_NAME dimensions
Dimensions that end in _NAME display a human-readable name for the value. This name
gets translated according to the locale in the report request, where appropriate. If the dimension
refers to an entity in an AdSense account, it will use the user-defined name for that
entity.