Esri EGMP2201 Exam Questions

For a large government organization requiring an equivalent data presence in a standby data center, database replication is the ideal solution.

1. What is Database Replication?

Database replication involves duplicating data from a primary database to a secondary database in near real-time or on a scheduled basis.

This ensures that both databases are synchronized and capable of serving data if one fails.

2. Why Database Replication Fits the Requirement

Standby Data Center: Database replication provides a fully equivalent copy of the data in the secondary data center.

High Availability and Disaster Recovery: If the primary database is unavailable, the standby database can immediately take over, ensuring business continuity.

3. Why Not Other Options?

Geodatabase Replication:

While it is designed for replicating geodatabase content, it is typically used for GIS-specific workflows, such as syncing field edits. It does not ensure equivalence for non-spatial components of the database.

It is not ideal for large-scale, organization-wide replication needs.

Disconnected Synchronization:

This is used in offline editing workflows where devices sync their edits with a central database at a later time. It is not suitable for maintaining an equivalent standby database.

4. Types of Database Replication

Asynchronous Replication: Updates are replicated at scheduled intervals, offering flexibility but with slight delays.

Synchronous Replication: Updates occur in real-time, ensuring both databases are always identical.

Steps to Implement Database Replication:

Configure the primary and standby databases in the organization's DBMS (e.g., SQL Server, PostgreSQL, Oracle).

Use the DBMS's built-in replication tools (e.g., SQL Server's Always On, PostgreSQL's Streaming Replication).

Set up monitoring to ensure the replication process is functioning correctly.

Reference from Esri Documentation and Learning Resources:

Database Replication in DBMS

Disaster Recovery with Database Replication

Conclusion:

Database replication is the recommended technology to establish an equivalent data presence in a standby data center, ensuring high availability and disaster recovery.

The issue arises because the standard database view is based on the base table of the points feature class, which does not include edits made in child versions. To resolve this, the database view must reference a versioned view to reflect changes in the Default version.

1. What Is a Versioned View?

A versioned view is created when a feature class is registered as versioned.

It allows querying and editing versioned data, including edits made in the Default version and child versions.

A standard database view does not account for the Adds and Deletes delta tables used in versioning, which is why edits are not visible.

2. Why Alter the View to Use a Versioned View?

By modifying the standard database view to reference the versioned view, the published web layer will reflect changes made in the Default version, including ongoing edits.

This ensures that updates to the points feature class are visible in the web layer without requiring manual intervention.

3. Why Not Other Options?

Have All Editors Reconcile and Post Points Edits to Default:

While this ensures edits are moved to the Default version, it requires continuous manual reconciliation and posting, which is impractical for a frequently edited dataset.

Rebuild Indexes and Calculate Database Statistics on Points:

These actions improve query performance but do not address the core issue of the standard view not reflecting versioned edits.

Steps to Alter the View:

Identify the versioned view associated with the points feature class. It typically has a name like points_EVW.

Modify the SQL for the existing view to reference the versioned view:

CREATE OR REPLACE VIEW points_web AS

SELECT <fields> FROM points_EVW;

Update the web layer to use the modified view as the data source.

Test the web layer to confirm that edits made to the Default version are now visible.

Reference from Esri Documentation and Learning Resources:

Publishing Data from Views

Conclusion:

To ensure edits made to the points feature class are visible in the web layer, the database view should be altered to reference the versioned view, which accounts for edits in the Default version.

To ensure that the parent geodatabase can be fully compressed, even with unacknowledged data change messages, the replication must be configured to replicate only the base tables.

1. What Happens with Unacknowledged Messages?

In traditional one-way replication, unacknowledged data change messages in the delta tables (Adds and Deletes) prevent full compression of the parent geodatabase.

By replicating only the base tables, the replication avoids using delta tables entirely, allowing the geodatabase to be fully compressed.

2. Why Replicate Only the Base Tables?

No Dependency on Delta Tables: This configuration ensures that the replication is based directly on the base table contents. As changes are not recorded in delta tables for replication, the parent geodatabase can be fully compressed without any impact.

Read-Only Copies: The replicated data in the child geodatabase will be read-only, which aligns with the requirement for regional offices.

3. Why Not Other Options?

Use the Full Replica Access Type:

Full replica access allows editing in the child geodatabase, which is unnecessary for read-only requirements. It also uses delta tables, preventing full compression.

Use the Archiving Option:

Archiving tracks historical edits and is unrelated to the replication or compression process. It does not solve the problem of unacknowledged messages blocking compression.

Steps to Set Up One-Way Replication with Base Tables:

Open ArcGIS Pro and connect to the parent geodatabase.

Use the Create Replica tool and select One-Way Replication.

Choose the option to replicate base tables only during the configuration process.

Define the datasets to replicate and complete the replication setup.

Reference from Esri Documentation and Learning Resources:

One-Way Replication Overview

Compressing Enterprise Geodatabases

Conclusion:

Configuring replication to replicate only the base tables ensures that the parent geodatabase can be fully compressed, even with unacknowledged data change messages.

When a database view is registered with the geodatabase, the geometry type, spatial reference, and row ID field are added to the geodatabase system tables. This enables ArcGIS to recognize and use the view effectively.

1. What Happens During Registration?

System Table Updates: Registering the view adds metadata to the geodatabase system tables, including:

The geometry type (e.g., point, polygon).

The spatial reference (coordinate system).

The row ID field used to uniquely identify rows.

This metadata ensures that the database view is treated as a spatial dataset within ArcGIS.

2. Benefits of Registration:

Spatial Functionality: Registered views can be used in ArcGIS for visualization, analysis, and querying.

Geodatabase Tools Compatibility: Tools like attribute editing and symbology work seamlessly with registered views.

3. Why Not Other Options?

Viewers Can Modify Which Fields Are Visible for the Database View:

The visibility of fields in a database view is determined by the SQL query used to create the view, not by the registration process.

The Registration Process Allows the Database Contents View to Be Edited Using ArcGIS Tools:

Registered views remain read-only in ArcGIS, regardless of registration. Registration does not allow editing the view's contents.

Steps to Register a Database View with the Geodatabase:

Open ArcGIS Pro and connect to the database.

Use the Register With Geodatabase tool.

Specify the database view to be registered.

Confirm that the geometry type, spatial reference, and row ID field are properly recognized.

Reference from Esri Documentation and Learning Resources:

Registering Views with the Geodatabase

Geodatabase Metadata

Conclusion:

Registering a database view with the geodatabase ensures that the geometry type, spatial reference, and row ID field are added to the system tables for reference, enabling ArcGIS to treat the view as a spatial dataset.

Geometric networks are not supported in branch versioning or workflows where edits are moved directly to the base table. Therefore, traditional versioning without move edits to base is the only viable option for implementing an offline mobile editing workflow with feature classes that participate in a geometric network.

1. Why Use Traditional Versioning Without Move Edits to Base?

Support for Geometric Networks:

Geometric networks are only compatible with traditional versioning workflows. Branch versioning does not support geometric networks, and using the 'move edits to base' option bypasses the versioning framework required for geometric networks.

Offline Mobile Editing:

Traditional versioning supports creating replicas that allow offline editing and subsequent synchronization. This workflow is critical for mobile editing scenarios.

2. Why Not Other Options?

Branch Versioning:

Branch versioning is designed for feature services and web-based workflows but does not support geometric networks.

Traditional Versioning with Move Edits to Base:

This option moves edits directly to the base table, which is incompatible with geometric networks and versioning workflows that require offline editing.

Steps to Configure Traditional Versioning Without Move Edits to Base:

Register the feature classes and datasets (including geometric networks) with traditional versioning in ArcGIS Pro.

Create a replica to support offline editing workflows.

Synchronize edits back to the geodatabase after offline editing, reconcile, and post to integrate changes into the Default version.

Reference from Esri Documentation and Learning Resources:

Traditional Versioning Overview

Geometric Networks and Versioning

Conclusion:

Using traditional versioning without move edits to base is the only method that supports offline mobile editing workflows while maintaining compatibility with geometric networks.