GUID Registry entries

By default, GUID auto-generation is disabled for all modules.

In order to enable auto-generation of GUIDs in a module (or system-wide), two GUID Registry entries must be specified:

  • GUID Enabled Registry entry must be set to true

    -AND-

  • GUID Auto Types Registry entry must specify which GUID type(s) to generate. Currently only UUID4 is supported.

On record save EMu checks whether the GUIDs table includes an entry for each type specified in the GUID Auto Types Registry entry, and generates a GUID for each type that is missing.

Currently EMu will auto-generate a UUID Version 4 GUID if one has not already been added to the record's GUIDs table.

Enable / disable auto-generation of GUIDs for a table or system-wide.

Description

By default auto-generation of GUIDs is disabled. With this Registry entry, it is possible to enable GUID support on a per table or system-wide basis.

Note: In order to enable auto-generation of GUIDs on record save, a GUID Auto Types Registry entry must also specify which GUID type(s) to generate. Currently only UUID4 is supported.

Usage

This Registry entry is assigned at the system level only:

Key System
Key 1 System
Key 2 Setting
Key 3 Table
Key 4 table or Default
Key 5 GUID Enabled
Value boolean
System Setting Table table or Default GUID Enabled boolean

where:

table

is the back-end name of an EMu module; or use Default for all modules.

boolean

is true (auto-generation of GUIDs is enabled) or false (auto-generation of GUIDs is disabled).

Note: In the absence of this entry, a setting of false is assumed.

Example

This entry specifies that auto-generation of GUIDs is enabled for the Catalogue module:

Key Setting
Key 1 System
Key 2 Setting
Key 3 Table
Key 4 ecatalogue
Key 5 GUID Enabled
Value true

This entry specifies that auto-generation of GUIDs is disabled for all modules:

Key Setting
Key 1 System
Key 2 Setting
Key 3 Table
Key 4 Default
Key 5 GUID Enabled
Value false

Specify which GUID variant is used when auto-generating a GUID on record save. Auto-generation of GUIDs also requires the GUID Enabled Registry entry to be set to true.

Description

EMu can auto-generate GUID values on record save. Currently, GUIDs are auto-generated in compliance with UUID Version 4.

The GUID Enabled Registry entry specifies whether GUID support is enabled for a table or system-wide (by default GUID support is disabled). The GUID Auto Types Registry entry specifies which GUID formats are to be auto-generated. In theory more than one variant can be used to specify the auto-generated GUIDs but EMu currently supports only UUID Version 4.

For more details see:

A UUID is a 128 bit quantity typically represented in text as a 32 character hexadecimal string with hyphen separators at set positions. For example:

84b567d5-dbbd-468a-be12-770747ebc397

71820e9a-1eb0-4b02-9382-20de614fbcdc

UUID Version 4 is an extensively used GUID generation method that provides a randomly generated GUID with infinitesimal probability of a duplicate. A prime advantage of this scheme is that GUIDs can be generated quickly and locally on demand without contacting a central naming authority or having to pre-allocate identifiers.

A UUID can be represented simply as a Uniform Resource Name (URN). For example:

urn:uuid:84b567d5-dbbd-468a-be12-770747ebc397

urn:uuid:71820e9a-1eb0-4b02-9382-20de614fbcdc

The URN name space identifier of uuid is used.

Refer to:

Note: EMu's GUID support is extensible and it is possible for organizations to substitute or extend the base EMu code to generate other or additional GUIDs. Please contact EMu Support for details.

Usage

This Registry entry is assigned at the system level only:

Key System
Key 1 System
Key 2 Setting
Key 3 Table
Key 4 table or Default
Key 5 GUID Auto Types
Value type;type;...
System Setting Table table or Default GUID Auto Types type;type;...

where:

table

is the back-end name of an EMu module; or use Default for all modules.

type;type;...

is a semicolon separated list of GUID variants.

Note: Currently only UUID Version 4 is supported.

Example

This entry specifies that when a GUID is auto-generated on record save in all modules that support GUID, the number generated will comply with the UUID Version 4 variant:

Key Setting
Key 1 System
Key 2 Setting
Key 3 Table
Key 4 Default
Key 5 GUID Auto Types
Value UUID4