SQL-001: Retrieve help text by application code and reference key

This statement retrieves a single help entry — its reference-key description and free-text help body — by joining APPLICATION_HELP_MASTER to APPLICATION_HELP_DETAIL on the reference key value, filtered by application code and reference key value. It backs clsHelpText.GetHelpText, which feeds the HoverHelp control's content.

Classification

Field	Value
SQL ID	SQL-001
Operation type	Read
Execution method	Inline SQL (VB & _ string concatenation)
Database	Oracle
Schema	[unqualified]**
Command type	Text
Business object	clsHelpText
Criteria property	RetrieveSQL
Lifecycle method	BeforeRetrieve / AfterRetrieve

Parameters

Parameter	Direction	Type	Max length	Description
:ApplicationCode	Input	String	5	Application code identifying the owning application; supplied to clsHelpText.GetHelpText(dpi, inApplicationCode, inReferenceKeyValue). Bound in BeforeRetrieve via DataRequest.AddParm("ApplicationCode", MyCriteria.ApplicationCode, 5).
:ReferenceKeyValue	Input	String	40	Reference key identifying the specific help entry (typically a control/field key). Bound in BeforeRetrieve via DataRequest.AddParm("ReferenceKeyValue", MyCriteria.ReferenceKeyValue, 40).

Tables

Table	Access	Columns used
APPLICATION_HELP_MASTER	SELECT, JOIN	APPLICATION_CODE, REFERENCE_KEY_DESCR, REFERENCE_KEY_VALUE
APPLICATION_HELP_DETAIL	SELECT, JOIN	HELP_TEXT, REFERENCE_KEY_VALUE

Sample SQL

-- Retrieve one help entry by application code and reference key
Select
  APPLICATION_HELP_MASTER.APPLICATION_CODE as ApplicationCode,
  APPLICATION_HELP_MASTER.REFERENCE_KEY_DESCR as ReferenceKeyDescription,
  APPLICATION_HELP_MASTER.REFERENCE_KEY_VALUE as ReferenceKeyValue,
  APPLICATION_HELP_DETAIL.HELP_TEXT as HelpText
From
  APPLICATION_HELP_MASTER,
  APPLICATION_HELP_DETAIL
Where
  APPLICATION_HELP_MASTER.REFERENCE_KEY_VALUE = APPLICATION_HELP_DETAIL.REFERENCE_KEY_VALUE
  AND APPLICATION_HELP_MASTER.APPLICATION_CODE = :ApplicationCode
  AND APPLICATION_HELP_MASTER.REFERENCE_KEY_VALUE = :ReferenceKeyValue

Operations and processes

• Load help text from the database

Business rules

• BR-AJAX-017: Help text is identified by an application code and reference key with length ceilings
• BR-AJAX-018: Help content is assembled by joining master and detail on the reference key
• BR-AJAX-019: A help lookup that matches nothing yields empty text, not an error
• BR-AJAX-020: Filling a help control with a null help object leaves content unchanged

Sources

• SAIF.Presentation.Web.Controls.AJAX.Infragistics111/clsHelpText.vb