Subordinate Objects

DataSource

DataSource is a subordinate object used to define the primary data source for the view or data sources defined in relationships. It will create groups of DS_Item and DS_Link objects to do this. The main DataSource object corresponds to a record in the pvxview.src file.

For information on the pvxview.src file structure, see Views System File Structures. Properties are read only and are set using corresponding Setxxx( ) methods.

DataSource Properties

The following table lists the properties of the DataSource subordinate object:

Property

Description

Description$

Data source name - short description of data source (used to identify the data source).

Expression_Ind$

Expression indicator for PrimarySource$.

"=" denotes PrimarySource$ contains an expression to be evaluated.

A blank indicates that the value of PrimarySource$ is a fixed value (Default).

InternalID$

Internal identifier for the data source.

InitLogicType$

Single character string indicating logic type:

C	Call
X	Execute
I or blank	Ignore *(Default)*

InitLogic$

Logic to be executed when a data source object is established. Reference based on InitLogicType$.

If type C, InitLogic$ contains program; entrypoint.

If type X, InitLogic$ contains PxPlus statement(s) to be executed. String, 128 characters. See Logic Procedures.

CloseLogicType$

Same as for InitLogicType$.

CloseLogic$

Logic to be executed when a data source object is dropped. See Logic Procedures.

LongDescription$

Long description for storing notes about the data source.

LogicObject$

Object specified to supply logic references. See Logic Procedures.

PrimarySource$

Primary data source, contents of this property vary according to SourceType$: Logical file name (L), File name (P), Object name;tableID (O), or External database table connection string (T).

SourceType$

Source type indicator:

L	PxPlus file identified by logical name.
P	PxPlus file identified by path name or prefix file reference to an external database table (PxPlus SQL ODBC Driver, ADO, Oracle, MySQL or DB2).
O	Custom data source object.
T	External database table.
D	Disabled source.

Src

Object identifier to the data source driver associated with the data source (e.g. *views/logio, *views/fileio or any custom data source object).

UpdateStamp$

Last update.

The following items are object Groups (*obj/group) that define a list of related objects:

DS_Item

Standard group of DS_Item objects. One object for each item defined in the data source.

DS_Link

Standard group list of DS_Link objects. One object for each link used by the DataSource.

DataSource Methods

The following table lists the methods of the DataSource subordinate object:

Method	Description
AddItem([ColumnName$ \| " * " ])	*(Internal Use Only)* Create a new DS_Item object. If a column name (no trailing "$") is supplied, the item object is initialized with information derived from the data source driver. If an *asterisk is supplied, all columns in the source will be added. Use ViewCtl equivalent.
AddLink( )	*(Internal Use Only)* Create a new DS_Link object. Use ViewCtl equivalent.
Clear( )	Re-initialize the data source object and delete all subordinate objects.
ClearItems( )	*(Internal Use Only)* Remove subordinate DS_Item objects.
ClearLinks( )	*(Internal Use Only)* Remove subordinate DS_Link objects.
GetItem(Item$ \| idx)	Return the DS_Item object handle for the specified item. If Item$ is used, the method will attempt to match it to both the item description and name.
GetItemCount( )	Return the number of items in the data source.
GetItemIndex(Item$)	Return the DS_Item group index for the specified item. (Name or description may be used.)
GetLink(LinkDesc$ \| idx)	Return the object identifier for the specified DS_Link object.
GetLinkCount( )	Return the number of links defined for the data source.
GetLinkIndex(LinkDesc$)	Return the DS_Link group index for the specified link.
RemoveItem(Item$ \| idx)	*(Internal Use Only)* Remove the specified DS_Item object. If Item$ is used, the method will attempt to match it to both the item description and name. Use ViewCtl equivalent.
RemoveLink(LinkDesc$ \| idx)	*(Internal Use Only)* Remove the specified DS_Link object. Use ViewCtl equivalent.
SetCloseLogic (Type$,Logic$)	Set CloseLogic$.
SetDescription(Description$)	*(Internal Use Only)* Set description of data source (used to identify the data source). Use ViewCtl equivalent.
SetInitLogic(Type$,Logic$)	Set InitLogic$.
SetInternalID(InternalID$)	*(Internal Use Only)* Set internal identifier for the data source.
SetLogicObject(ObjNm$)	Set LogicObject$.
SetLongDescription$(LongDesc$)	Set long description for storing notes about the data source.
SetPrimarySource(SrcType$,SrcName$,Expr)	Set SourceType$ and PrimarySource$. Expr is either X or " " null.
SetUpdateStamp(Stamp$)	*(Internal Use Only)* Set date/time stamp of last update.