Records Created On Service Now Instances by Precision Bridge

In order to complete migrations, Precision Bridge will create several objects on the ServiceNow instances. These objects are only created 'On Demand' meaning that they will only be created when the piece of functionality using them is executed.

This article details what these objects are, and what their function is.

Scripted Soap Web Services

There are several web services that Precision Bridge makes use of to perform complex operations that are not easily supported by the standard ServiceNow API. These web services will only be created on demand and may be updated automatically if the version of Precision Bridge is updated. All web services created by precision Bridge will have the following format u_pb_<ws name>_<vs version>.

The table below lists the web services that may be created.

Name	Description	Found on Server(s)
u_pb_getAttachment_<version>	Retrieves attachment data. The attachment content is encoded using Base 64.	Source
u_pb_sync_import_set_ws_ <version>	Creates or Updates Import Sets and Transform maps used to migrate data onto the target server.	Target
u_pb_create_table_ws_ <version>	Creates tables. This is used by the Archiving Wizard and when Generating Form Mappings, where ServiceNow is the Target.	Target
u_pb_create_custom_fields_ <version>	Used to create the ServiceNow Reporting Tables, where ServiceNow is used as the Reporting Server. Also used in Generating Form Mappings, where ServiceNow is the Target.	Reporting Server and Target
u_pb_mig_attach_<version>	Used to 'Pull' attachments directly from the source server. This will be used in ServiceNow instance migration projects where the Server-Server Attachment Migration option is used.	Target
u_pb_CheckForCascadeDeletes_ <version>	This is only used when Source Deletions are enabled. It will check the target server to see if any records that will be deleted as part of a cascade delete exist.	Source
u_pb_DeleteRecordBatch_ <version>	This is only used where Source Deletion is enabled (for example in an Archiving Use case) Deletes a batch of records from a table.	Source
u_pb_getServerMetadata_ <version>	Used to obtain metadata about the server such as a list of data types, tables, applications and server settings such as time zone.  This metadata is used in both the design and execution of projects.	Source, Target and External Lookup Server
u_pb_getTableIndexData_ <version>	This is used in the Archiving Wizard when the target is a database and there is a requirement to replicate the indexes that exist on the ServiceNow source table. Used to obtain Index data about a table.	Source
u_pb_GetDisplayValue_<version>	This is used to support the ID Replacement mapping type. Obtains display values for a set of table/sys_id values.	Source
u_pb_GetSysIDFromDisplayValue_ <version>	This is used to support the ID Replacement mapping type. Obtains the sys Id of a set of records given the table name and display values.	Target
u_pb_GetTransformMap SynchronisationData_<version>	This is used in execution initialisation to check if the import sets and/or transform maps need to be updated due to changes in the fields on the base table.	Target

 

Import Sets and Transform Maps

These are created on the target server for each table that is a migration target. Precision Bridge will create an import set table called pb_<table name>. This import set table will be automatically checked on each execution, and updated if fields are added or deleted from the underlying table.  The import set table name may be truncated if the actual name of the underlying table is too long. 

In addition to the import set, a transform map with the same name as its import set will be created. This may use a script to insert the data into the final table, or a set of field mappings. This depends on the Migration Method used (see Migration Execution Options) Again, this will be checked and updated if fields are added or deleted from the underlying table.

The import sets and transform maps support the migration of  data into the target instance in a performance efficient and reliable way. ServiceNow recommends this approach rather than directly pushing data to the target table.

Additional Import Sets and Transform Maps for Virtual Tables

All virtual tables defined by Precision Bridge will have an associated import set table and transform map. In addition, a dummy target table named u_pb_dummy_import_set_target will be created.

This table's only purpose is to act as a target for the transform map (where a target is mandatory), though the transform map will actually write and update data, potentially to multiple tables, to perform the function of the virtual table and will not actually write or update records in the u_pb_dummy_import_set_target table.

ACL's and Role

Any import set tables created by Precision Bridge will also generate the required  ACL's for CRUD operations. All ACL's will be assigned only to the role pb_migrator. This role will also be created on demand if it is found not to exist.

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