GetClassObjectRange - Teradata Meta Data Services

GetClassObjectRange

Purpose

The CMetaObject class GetClassObjectRange returns the specified subset of CMetaObjects in the class that matches the selection criteria. The GetClassObjectRange only returns the current version for objects matching the search criteria.

Description

The function allows the programmer to specify the property id, property value and comparison operator on which to perform the search. The properties upon which to sort the returned list can also be specified. This function allows specifying the start number and number of objects to return. The properties to be returned can be restricted by using a columns filter.

For more information on building the strObjName parameter for a search, see “Name Search” on page 131.

For more information on building the sortList parameter, see “Sort List” on page 130.

For more information on using the columnFilters parameter, see “Column Filter” on page 132.

Requirements

The class ID (internal or globally unique) must be set.

The propFilter list may contain zero or more CMetaFilterInfo objects.

The PropertyID (SetPropertyID()) or PropertyName (SetName()) of the value attribute in each CMetaFilterInfo object must contain a valid Relative Property ID or name of a property description in the class.

The value attribute in each CMetaFilterInfo object must also be set to the value on which the search will be made. This value must be of the same type as the property description. For example, if the search is to be made on Relative Property ID = 1 and Relative Property ID 1 is defined as an integer, Value must be set to an integer (SetInt()). If relative Property ID 1 is a string, Value must be set to a string (SetString()).

The default ComparisonOperator in each CMetaFilterInfo object is EQUAL and the default LogicalOperator is META_AND.

If the propFilter list contains zero objects, the function will perform a search by strObjName only. If strObjName is also NULL, the API will return all the objects in the collection.

If the propFilter list contains objects and strObjName is set, the logical operator between the properties and the name will the “AND”. To perform a search of a name “OR” a property, set strObjName to NULL and add a CMetaFilterInfo object to the propFilter list for a name search.

Syntax

HRESULT GetClassObjectRange (

vector<CMetaObject>&objectList,

int *totalCount,

const MetaFilterInfoVector &propFilter,

const MetaObjectKeyVector &sortList,

const int startNum, 

const int returnCount,

const GUID &gClassID, 

const OBJECTID_t lClassID = 0,

LPCTSTR strObjName = NULL, 

const bool WithLock = false);

HRESULT GetClassObjectRange (

vector<CMetaObject>&objectList,

int *totalCount,

const MetaFilterInfoVector &propFilter,

const MetaObjectKeyVector &sortList,

const MetaObjectIDVector &columnFilters

const int startNum, 

const int returnCount,

const GUID &gClassID, 

const OBJECTID_t lClassID = 0,

LPCTSTR strObjName = NULL, 

const bool WithLock = false);

See Table 50 for examples of setting the startNum and returnCount.

Table 50: GetClassObjectRange Example 

Total # of objects in search results	Start Number	Return Count	Number of objects returned	Objects returned
100	1	20	20	1-20
100	41	50	50	41-90
100	91	20	10	91-100
100	200	20	0
0	20	20	0

For more information on creating the propFilter for the search, see Chapter 8: “CMetaFilterInfo Class.”

For more information on using the columnFilters parameter, see “Column Filter” on page 132.

Argument	In/Out	Description
objectList	In/out	Reference to the list of CMetaObjects that will hold the collection returned. The list is cleared before adding the return collection.
totalCount	out	Returns the total number of objects that were in the search results. Set totalCount to NULL if you do not want the total.
propFilter	In	List of FilterInfo objects containing the property id and value to use to perform the search
sortList	In	List of property identifiers (relative property id or name) to sort the collection by. The return list will be returned in ascending order and the sort will not be case specific.
columnFilters	In	List of property IDs defining the common and unique properties to be set in each object. An empty vector means to return all properties.
gClassID	In	Class GUID.
lClassID	In	Class internal ID.
StrObjName	In (optional)	Search string for names of objects in the class to be returned.
WithLock	In	WithLock=true keeps the class table locked for WRITE. Use within an explicit transaction. Set WithLock to true when one of the class objects will subsequently be updated within the transaction. This prevents deadlocks caused by Teradata promotional locks.