guiyanakuang commented on issue #1644: URL: https://github.com/apache/orc/issues/1644#issuecomment-1790253172
@neopaf. I can’t find any relevant reading material either. At the moment it seems that looking at the source code is the most direct way to go. https://github.com/apache/orc/blob/24beffb6fed6d408e25654e53c255f564c8bd8a9/java/core/src/java/org/apache/orc/impl/writer/ListTreeWriter.java#L78-L93 This is the writing process of array column. 83: Record array length 84: Write child column The `array` column records the length of the array `lengths`. When reading `v` sequentially, we can assemble the array according to how many `v` are taken according to `lengths`. You can look at StructTreeWriter and other writers to see how this is stored. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
