Do you work in an environment where a Teradata compression tool is installed that conforms to your satisfaction? If not, I assume you are probably not very pleased with having to walk your way through the databases, table by table, to find out what to compress on which column. Typically, this is time-consuming, fatiguing, and

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The importance of the PDM Compression is a popular way of saving IOs, by allowing to pack more rows into each data block. Data blocks are the smallest unit transferred between hard drives and main memory, the most expensive operation in any database system. Compression can be done automatically by the system (block level compression)

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Multivalue compression and the indication of nullability are different matters, but with one common task: Collecting information about column values in every row. To keep space requirements low, Teradata stores information about nullability and multivalue compress in the so-called presence bytes. The alert reader might recognize that the name “presence byte” suggests that it indicates

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Even though stage tables are only temporary objects, holding intermediate data, a conventional table design can differentiate between a good performing load and a load proceeding at a snail’s pace. The additional efforts are paying off soon. The correct choice of data types and sizes is essential. Some bytes have to be pushed into Teradata,

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The Teradata DBMS has always supported compression in a (growing) number of forms. Version 5.0 introduced Multi-Value Compression (MVC), version 13.10 introduced Algorithmic (ALC) and Block Level (BLC) compression, and version 14.0 introduced multiple automatic compression options for Columnar tables. These can produce disk space and associated performance savings; however, implementing Teradata compression with MVC

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Whenever you have to analyze a huge Teradata table regarding Multivalue compression, this is a costly operation from a workload point of view. Unfortunately, Teradata (the company) does not offer any tool which would allow automatizing this task. Usually, analysis requires counting the number of distinct values per table column. Counting is resource and time

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