Extended Events - Pro SQL Server Internals - page 548

Figure 28-10. Extended Events actions
Types and Maps
In the Extended Events framework, data attributes are strongly typed with either types or maps. Types represent scalar
data types, such as integer, character, or GUID. Maps , on the other hand, are enumerators that convert integer keys
into a human-readable representation.
You can think of wait types as an example of Extended Events maps. The list of available wait types is pre-defined,
and SQL Server can return an integer wait type key with events. The wait_types map allows you to convert this code
into an easy-to-understand wait type definition.
You can see the list of available types and maps by using the query shown in Listing 28-7. Figure 28-11 shows the
partial output of the query when run in SQL Server 2012.
Listing 28-7. Examining types and maps
select
xo.object_type as [Object]
,xo.name
,xo.description
,xo.type_name
,xo.type_size
from
sys.dm_xe_objects xo
where
xo.object_type in ('type','map')