What are essential Oracle SQL developer preference settings for optimal query performance?

 When using Oracle SQL Developer for optimal query performance, there are a few key preference settings and configuration adjustments you can make to improve your workflow, make queries run more efficiently, and minimize unnecessary load on your database. These settings are largely focused on the execution environment, query optimization, and resource management. Here’s a breakdown of the essential settings to configure in Oracle SQL Developer:

1. SQL Execution Settings

• Run Statements in Parallel (via Execution Plans): Ensure you’re executing queries with parallel processing capabilities enabled, where appropriate.
  • Navigate to Preferences > Database > SQL Execution.
  • Enable Run SQL Statements in Parallel if your system supports parallel execution and your queries are suitable for it.
• Query Results: Display Execution Plan:
  • Show execution plans to analyze performance bottlenecks.
  • Go to Preferences > Database > Query Results and check Display Execution Plan so you can immediately review how Oracle executes your query.
• Limit Query Execution Time:
  • To avoid queries running indefinitely (especially if you're testing), you can set a time-out for SQL execution.
  • Under Preferences > Database > SQL Execution, set a timeout value under SQL Execution Timeout (e.g., 120 seconds).

2. Connection Settings

• Connection Pooling: If you're using multiple connections to the same database, enabling connection pooling can reduce overhead and improve response times.

  • Navigate to Preferences > Database > Advanced.
  • Enable Use Connection Pooling and set optimal pool sizes.

• Disable Auto-commit (if not required): Auto-commit can create unnecessary transactions, potentially affecting performance.

  • Go to Preferences > Database > Transaction.
  • Disable Auto-commit and use explicit commit statements in your code when necessary.

3. SQL Formatter and Code Insight

• SQL Formatting (for readability): While this doesn't directly affect performance, better formatting can help you write more efficient queries.
  • Navigate to Preferences > Code Editor > SQL Formatter and set formatting options to align your code for better readability.
• Code Insight and Auto-Completion:
  • Enable Code Insight to help you quickly write accurate SQL code. It can save time and reduce errors that could lead to inefficient queries.
  • Go to Preferences > Code Editor > Code Completion and ensure Enable Auto Completion is checked.

4. Result Set Settings

• Limit Rows Returned in Query Result:

  • By limiting the number of rows returned, you can avoid loading excessive data, which can negatively affect the UI and performance.
  • In Preferences > Database > Query Results, you can set the Max Rows to a reasonable number (e.g., 500 or 1000) to avoid fetching too many rows.

• Fetching Large Results in Batches:

  • If you work with very large result sets, set the fetch batch size to retrieve results in smaller chunks to avoid memory issues.
  • Go to Preferences > Database > Query Results and adjust the Row Fetch Size to a lower value like 1000 rows.

5. Query History and Caching

• Limit History Size: Large query histories can slow down SQL Developer, so limiting the number of past queries stored is a good idea.
  • Go to Preferences > Database > SQL History and limit the Maximum SQL History to a smaller number, such as 100 or 200.
• Use Result Caching: Enabling result caching can speed up the repeated execution of the same query.
  • Navigate to Preferences > Database > Advanced, and enable Enable Result Caching.

6. Database Object Management

• Lazy Load for Database Objects: To prevent unnecessary database metadata loading (which can slow down performance), use lazy loading for schema objects.
  • Go to Preferences > Database > Object Viewer and enable Lazy Load.
• Object and Data Fetching Limits: Limit the number of objects and data rows displayed when navigating through the schema.
  • Navigate to Preferences > Database > Object Browser and adjust limits for Max number of objects to display.

7. Auto-Refresh Behavior

• Disable Auto-Refresh: Turn off automatic refresh of database objects to reduce unnecessary queries against the database while you're working.
  • In Preferences > Database > Object Browser, disable the Auto Refresh option.

8. Network/Timeout Preferences

• Optimize Network Timeout: Adjust your Connection Timeout settings to prevent unnecessary waits for slow database responses.
  • In Preferences > Database > Advanced, set Connection Timeout to a reasonable value (e.g., 30 seconds).

9. Log and Debugging Preferences

• Limit Debugging Output: While debugging, excessive logging can slow down performance.
  • Go to Preferences > Database > Debugger and make sure debug output is only logged when necessary. This is important if you are debugging complex PL/SQL code.

10. Query Execution Feedback

• Show Query Execution Time: Enable this to measure the execution time of your queries, which can help you optimize long-running queries.
  • Navigate to Preferences > Database > Query Results, and check the option to Show Query Execution Time.

Additional Tips for Query Performance

• Enable Explain Plan for Queries: Always review the execution plan of your queries to identify inefficiencies.
  • In SQL Developer, you can easily get the execution plan by clicking on the "Explain Plan" tab before running the query.
• Analyze SQL with SQL Tuning Advisor: Use the Oracle SQL Tuning Advisor for analyzing and optimizing complex queries, and always check the Explain Plan of queries with high execution times.

By fine-tuning these settings in Oracle SQL Developer, you can create an optimal environment that improves query performance, reduces unnecessary database load, and enhances your productivity when working with SQL.