![]() We experimented with both of zlib and snappy algorithms that are available for Hive t ables. Vertica does not support LZO compression for these formats. ORC used lightweight compression algorithm e.g. For files in Parquet format, Vertica supports some complex types.įiles compressed by Hive or Impala require Zlib (GZIP) or Snappy compression. Take a look at this documentation for more information about how data is laid out. When you specify orc.compress SNAPPY the contents of the file are compressed using Snappy. Both Snappy & ZLIB compession codec are supported with ORC. Vertica supports all simple data types supported in Hive version 0.11 or later. 2 Answers Sorted by: 3 OrcFiles are binary files that are in a specialized format. Also while querying the ORC tables, aggregations like count, max, min, sum does not require to the MapReduce jobs as the ORC table itself store these aggregation as the columns level. The following example specifies that data in the table newtable be stored in ORC format using Snappy compression. ![]() If you export data from Vertica, consider exporting to one of these formats so that you can take advantage of their performance benefits when using external tables. Zlib is quicker than SNAPPY to read, smaller than SNAPPY on disk, but a bit slower than SNAPPY to write. In addition, to specifying the storage format, you can also specify a compression algorithms such as Zlib, Snappy, etc. ORC provides the best Hive performance overall. If you have ORC or Parquet data, you can take advantage of optimizations including partition pruning and predicate pushdown. For detailed information about ORC file format, click here. External tables with ORC or Parquet data therefore generally provide better performance then ones using delimited or other formats where the entire file must be scanned. The files contain metadata that allows Vertica to read only the portions that are needed for a query and to skip entire files. This means that if data is loaded into Big SQL using either the LOAD HADOOP or. CREATE TABLE newtable WITH ( format 'Parquet', writecompression 'SNAPPY' ) AS SELECT FROM oldtable The following example specifies that data in the table newtable be stored in ORC format using Snappy compression. ORC and Parquet, like ROS in Vertica, are columnar formats. By default Big SQL will use SNAPPY compression when writing into Parquet tables. JellyBook Announcing JellyBook version 1.1.7. These formats are common among Hadoop users but are not restricted to Hadoop you can place Parquet files on S3, for example. Among them, Vertica is optimized for two columnar formats, ORC (Optimized Row Columnar) and Parquet. You can create external tables for data in any format that COPY supports. ![]()
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