HListLink (Function)

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Deletion and modification rule

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HListLink (Function)

In french: HListeLiaison

Not available with this kind of connection

Returns the list of data file bindings (Merise type) present:

in the current analysis,
in ongoing analyses (case of projects with multiple analyses).
in a specific analysis.

Example

// Retrieve the links of the Customer data file in the current analysis
ListLink is string
ListLink = HListLink(Customer, hLstDetail)
// Adds the link list to the COMBO_MaCombo field
ListAdd(COMBO_MaCombo, LinkList)

// Retrieve the links of an HFSQL Client/Server database
// independently of the current analysis
CntHFSQL is Connection
CntHFSQL.Provider = hAccessHFClientServer
CntHFSQL.User = "admin"
CntHFSQL.Password = ""
CntHFSQL.Server = "HFSQLServer:4900"
CntHFSQL.Database = "CRM"
HOpenConnection(CntHFSQL)
ListLink is string = HListLink("*", CntHFSQL)
// Adds the list of links in COMBO_COMBO1
ListAdd(COMBO_COMBO1, ListLink)

Syntax

Listing the links in an analysis Hide the details

<Result> = HListLink([<Data file> [, <Path of the WDD file> [, <Password of the WDD file>]]] [, <Options>])

<Result>: Character string

List of links.
Multi-analysis projects: If several analyses are in progress, all links for all analyses in progress are listed (without duplicates).
The different link descriptions are separated by CR characters (Carriage Return). The result is more or less detailed depending on the constant used:
hLstDetail is not specified <Connection Name 1> + TAB + <Data File Name 1.1> + TAB + <Field Name 1.1> + TAB + <Cardinality 1.1> + TAB + <Data File Name 1.2> + TAB + <Field Name 1.2> + TAB + <Cardinality 1.2> + CR + ...
hLstDetail is specified <Link Name 1> + TAB + <Data File Name 1.1> + TAB + <Field Name 1.1> + TAB + <Cardinality 1.1> + TAB + <Data File Name 1.2> + TAB + <Field Name 1.2> + TAB + <Cardinality 1.2> + TAB + <Modification Rule> + TAB + <Deletion Rule> + CR + ...

Where:
<Nom Liaison X> Link name.
<Nom Fichier de données x.1> Name of data file on primary key side.
<Nom Rubrique x.1> Name of the item on the primary key side.
<Cardinalité x.1> Cardinality of the link on the primary key side, of the form "<Cardinalité min>,<Cardinalité max>" (for example "0,N" or "1,N").
<Nom Fichier de données x.2> Name of data file on foreign key side.
<Nom Rubrique x.2> Name of field on foreign key side.
<Cardinalité x.2> Cardinality of the foreign key link, of the form "<Cardinalité min>,<Cardinalité max>" (for example "0,N" or "1,N").
<Règle de modification> Rule to be applied when modifying the primary key.
<Règle de suppression> Rule to be applied if the primary key is deleted.
The name of data files corresponds to the name of the database + '\' + the relative physical name of these data files.
If one of the links listed is performed on a compound key, the <Nom Rubrique 1.2> parameter returned will correspond to the names of the various components of the key. The names will be separated by a comma.

<Data file>: Optional character string

Name of the data file whose links must be listed. The links originating from this file or ending at this file are listed.
If this parameter corresponds to "*", HListLink lists the links defined for all the data files in the analysis.

<Path of the WDD file>: Optional character string

Full path of the analysis file (.WDD file).
If this parameter is not specified or is equal to an empty string (""), the links are searched for:
in the current analysis.
in all current analyses (case of projects with multiple analyses).

<Password of the WDD file>: Optional character string or secret string

Password defined for the analysis. If no password is defined, this parameter must be an empty string ("").
New in version 2025
Secret strings: If you use the secret string vault, the type of secret string used for this parameter must be "Ansi or Unicode string".
To learn more about secret strings and how to use the vault, see Secret string vault.

<Options>: Optional integer constant

Type of list to perform:
hLstDetail Lists the detailed information about the links.
hLstNormal
(default value) Lists the links.
This parameter is ignored.

Listing the links of a data file accessible via Native Connector or OLE DB, or via an HFSQL Client/Server connection Hide the details

<Result> = HListLink([<Data file> [, <Connection>]] [, <Options>])

<Result>: Character string

List of links. The different link descriptions are separated by CR characters (Carriage Return). The result is more or less detailed depending on the constant used:
hLstDetail is not specified <Connection Name 1> + TAB + <Data File Name 1.1> + TAB + <Field Name 1.1> + TAB + <Cardinality 1.1> + TAB + <Data File Name 1.2> + TAB + <Field Name 1.2> + TAB + <Cardinality 1.2> + CR + ...
hLstDetail is specified <Link Name 1> + TAB + <Data File Name 1.1> + TAB + <Field Name 1.1> + TAB + <Cardinality 1.1> + TAB + <Data File Name 1.2> + TAB + <Field Name 1.2> + TAB + <Cardinality 1.2> + TAB + <Update Rule> + TAB + <Delete Rule> + CR + ...

Where:
<Nom Liaison X> link name.
<Nom Fichier de données x.1> Name of data file on primary key side.
<Nom Rubrique x.1> Primary key side field name or specified data file name.
<Cardinalité x.1> Cardinality of the link on the primary key side, of the form "<Cardinalité min>,<Cardinalité max>" (for example "0,N" or "1,N").
<Nom Fichier de données x.2> Name of data file on foreign key side.
<Nom Rubrique x.2> Name of field on foreign key side.
<Cardinalité x.2> Cardinality of the foreign key link, of the form "<Cardinalité min>,<Cardinalité max>" (for example "0,N" or "1,N").
<Règle de modification> Rule to be applied if the primary key is modified (see Remarks).
<Règle de suppression> Rule to be applied if the primary key is deleted (see Remarks).
The name of data files corresponds to the name of the database + '\' + the relative physical name of these data files.
If one of the listed links is performed in a composite key, the <Name item 1.2> parameter returned will correspond to the name of the different key components. The names will be separated by a comma.

<Data file>: Optional character string

Name of the data file whose links must be listed. The links originating from this file or ending at this file are listed.
If this parameter corresponds to "*", HListLink lists the links defined for all the data files in the analysis.
This parameter can correspond to a name unknown to the HFSQL engine, only existing on the database server.
The name of the data file found in first position corresponds to the data file related to the primary key.

<Connection>: Optional character string or Connection variable

Connection to use. This connection corresponds to:
the name of the connection defined in the data model editor or with HDescribeConnection or HOpenConnection.
the name of a variable of type Connection.

<Options>: Optional integer constant

Type of list to perform:
hLstDetail Lists the detailed information about the links.
hLstNormal
(default value) Lists the links.
This parameter is ignored.

Remarks

Deletion and modification rule

The modification and deletion rules returned by HListLink can correspond to the following constants:


hIntegrityCascade	Manage the cascading modification and deletion.
hIntegrityDefaultValue	During the deletion, a default value is assigned to the linked records.
hIntegrityForbidden	Strict respect of integrity.
hIntegrityNone	No integrity constraint.

Component: wd300hf.dll