Best Approach for Daily XML Processing and Database Updates

I have handle two XML files daily, each with a size of 50MB or more. These files are transferred via SFTP or FTP. Our goal is to extract specific values from these files, check their existence in our database, and either update existing records or insert new ones as necessary.

Requirements:

File Retrieval: Automate the retrieval of XML files from an SFTP or FTP server. Store the files temporarily within Appian or an external file storage service.

Data Extraction: Parse the XML files to extract a list of values. Given the large file sizes, efficient parsing and processing strategies are needed.

Data Validation and Update: Compare extracted values against existing database records. Update existing records with the latest values or insert new records as required.

Performance Considerations: Handle large files efficiently, possibly by processing in chunks. Ensure database operations (updates and inserts) are optimized for performance.

can any one suggest some best approach to do this.