When using SQL Loader to load data into an Oracle database, two important files are generated: the log file and the discard file. These files provide valuable information about the loading process and help identify any potential issues or errors encountered during the data loading process. In this article, we will discuss the purpose and content of these files.
Log File
The log file generated by SQL Loader contains detailed information about the loading process. It provides a summary of the number of records successfully loaded, rejected, or discarded. The log file also includes information about any errors encountered during the loading process, such as data format errors or constraint violations.
Content of Log File
The log file includes the following information:
- Control file details: Information about the control file used for the data loading process, including the table structure and data mapping.
- Input file details: Details of the input file being loaded, such as file path and format.
- Load statistics: Summary statistics on the number of records processed, loaded, and rejected.
- Error messages: If any errors occurred during the data loading process, they will be recorded in the log file along with the corresponding error message.
Discard File
The discard file generated by SQL Loader contains records that were rejected or discarded during the data loading process. These records are typically not loaded into the target table due to formatting errors, constraint violations, or other issues.
Content of Discard File
The discard file includes the following information:
- Rejected records: Records that failed to meet the data format requirements specified in the control file.
- Discarded records: Records that are intentionally discarded due to constraints or business rules specified in the control file.
- Error details: For each rejected or discarded record, the discard file includes the reason for rejection or discard.
Analyzing Log and Discard Files
To analyze the log and discard files generated by SQL Loader, follow these steps:
- Open the log file and review the summary statistics first. This will give you an overview of the load process, including the number of successful loads, rejected records, and any errors encountered.
- Look for error messages in the log file. Errors may indicate issues such as invalid data format or constraint violations.
- Open the discard file to investigate rejected or discarded records. Review the error details provided to understand the reason for rejection or discard.
By analyzing the log and discard files, you can gain insights into the data loading process and identify any issues that need to be addressed. This information can help you troubleshoot problems and ensure the successful loading of data into your Oracle database.
#tech #SQLLoader