getFileLength(): Decimal;
The getFileLength method of the DbFile class returns the size of the physical database file in bytes as a decimal value.
The maximum size of a database file is 2^64-1 (or approximately 16 Exabytes), which requires 19 digits of precision for storage. To handle up to the maximum possible database file size, you should use a Decimal[19] primitive type to receive the return value.
This method executes on a persistent server node, and is implemented and executed by the physical database engine.