SELECT Statement for Schema Queries
Schema data queries use the SELECT statement with a syntax similar to that for data queries. The difference is the use of a special class called "meta_class", which identifies the query as a schema query.
The following example requests all class definitions that are within the current namespace.
Schema queries only support "*". To narrow the scope of the definitions returned, a provider can add a WHERE clause that specifies a particular class.
The following example shows how to add a WHERE clause to specify a particular class.
The special property called __this identifies the target class for a schema query. Note that the ISA operator must be used with the __this property to request definitions for the subclasses of the target class. The preceding query returns the definition for the Win32_LogicalDisk class and definitions for all of its subclasses.
The following example shows how to request a class definition for a single class by using the __Class system property.