The MQCOLUMNSET structure specifies the number of queue properties to be retrieved from each queue and their property identifiers. You can specify any number of queue properties, from a single queue property to all the properties provided by MSMQ. MSMQ can return any number of queue properties to the single query.
typedef struct tagMQCOLUMNSET
{
ULONG cCol;
PROPID _RPC_FAR *aCol;
} MQCOLUMNSET;