The versionstored in the Postscript is the lowest version of Hive that isguaranteed to be able to read the file and it stored as a sequence ofthe major and minor version. The Postscript is nevercompressed and ends one byte before the end of the file. The Postscript section provides the necessary information to interpretthe rest of the file including the length of the file's Footer andMetadata sections, the version of the file, and the kind of generalcompression used (eg. encrypted stripe statistics: list of ColumnarStripeStatistics.The sections of the file tail are (and their protobuf message type): This documentincorporates the Protobuf definition from theORC source code and thereader is encouraged to review the Protobuf encoding if they need tounderstand the byte-level encoding The metadata for ORC is stored usingProtocol Buffers, which providesthe ability to add new fields without breaking readers. Thefile's tail consists of 3 parts the file metadata, file footer andpostscript. Theoverall structure of the file is given in the figure above. Since HDFS does not support changing the data in a file after it iswritten, ORC stores the top level index at the end of the file. Using pushdown filters from Hive, thefile reader can skip entire sets of rows that aren't important forthis query. Furthermore, ORC files include light weight indexes thatinclude the minimum and maximum values for each column in each set of10,000 rows and the entire file. ORCsupports projection, which selects subsets of the columns for reading,so that queries reading only one column read only the requiredbytes. However, storage savings are only part of the gain. Additionally, ORC can apply generic compression using zlib, orSnappy on top of the lightweight compression for even smallerfiles. ORCuses type specific readers and writers that provide light weightcompression techniques such as dictionary encoding, bit packing, deltaencoding, and run length encoding – resulting in dramatically smallerfiles. In Hive 0.11 weadded a new file format named Optimized Row Columnar (ORC) file thatuses and retains the type information from the table definition. However, RCFile has limitations because ittreats each column as a binary blob without semantics. Hive's RCFile was the standard format for storing tabular data inHadoop for several years. This version of the file format was originally released as part ofHive 0.12. A TV stlye RSS ticker extension for Firefox 1.5+. Download News Strip: RSS Reader for Firefox for free. Apple's new version has nothing inside the needle. Apple is changing its syringe emoji to remove the dripping blood, as it becomes widely used to talk about the Covid-19 vaccine. To read the news, it will open a browser. The goal of this tool is to offer the user a fast and cheap way to read news given by an RSS or ATOM feed by tray notifications. Read, share, star and search your favorite feeds by using clean and intuitive interface. Stripes is a minimalistic RSS reader created to help you enjoy your daily news. Download Stripes - RSS News Reader for macOS 10.11 or later and enjoy it on your Mac. Opt to receive notifications when news arrives, share news with friends, group stories by keyword, pin live tiles with the latest news, and play GIF animations and YouTube videos right. Relatively new to the RSS scene, the Newsflow reader and aggregator downloads news from RSS feeds directly to your computer in a sleek, appealing interface.
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