Hi,

The Developer Console is a collection of tools you can use to analyze and troubleshoot applications in your Salesforce organization. It’s a popup window composed of a set of related tools that allow you to access your source code and review how it executes. It can also be used to monitor database events, workflows, callouts, validation logic, cumulative resources used versus system limits, and other events that are recorded in debug logs. It’s a context-sensitive execution viewer, showing the source of an operation, what triggered that operation, and what occurred afterward.

Purpose:-

The Developer Console puts essential tools for editing code, debugging requests, and analyzing performance and memory usage in one place. You can use the Developer Console for a variety of administrative and development tasks, including:

General Debugging and Troubleshooting

The Developer Console provides mechanisms to inspect executed requests. It provides access to a fine-grained log, allowing you to review every statement executed within a request, and a set of interactive panels that let you simulate an execution “step-through.”

The Developer Console provides a convenient set of tools to efficiently track down logical issues. For example, if you want to understand why a certain request generates an “Attempt to de-reference a null object” error, you can review the execution, identify the offending logic, and set a heap dump capture marker at that point. You can then execute the process again, and inspect the request at that specific point in the execution to understand in detail how to improve your code. While the Developer Console can't pause execution like a traditional debugger, it provides cloud developers much of the same visibility, and reduces the need to instrument code with System.debug commands. And unlike a traditional debugger, you can examine the execution both forward and backwards.

Source Code Editing and Navigation

The Developer Console allows you to create and edit source code within the Developer Console itself, letting you inspect, trace, and edit your code all in the same tool. The Repository tab allows you to quickly browse through and open your source code. You can open a working set of source code views and switch between them with a single click. You can open and edit Apex triggers, classes, and Visualforce pages and components, and you can open a read-only view of your object definitions. You can also navigate the contents of packages created in your organization.

Performance Validation

The Developer Console has a number of panels dedicated to the inspection of performance. Open a debug log and view the aggregated performance of an operation in the Performance Tree. Review the Executed Units tab, which breaks up the request both by time and type. This tab categorizes the timings by methods, queries, workflows, callouts, DML, validations, triggers, and pages, which gives you a clear idea of where to find performance issues. The Timeline tab provides a timeline view of the overall request. Within this view, you can review .

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