How Do I Select The Appropriate Data Type In Teradata? Datatype conversions are very costly and can require a lot of CPU on large tables. The wrong selection of datatypes has a negative effect on the execution plan. In this article, I will explain the details and how to get optimal performance from your queries

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Teradata Table Design Checklist The creation of tables in an ever-recurring task, so I thought it was time to offer a checklist. Primary Index or NOPI? Is the Primary Index distributing rows evenly? Is the correct character set used? Are character set and data types matching across tables? Can the Primary Index be unique? Should

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As a Teradata SQL tuner, most of the time, we have to deal with skew. In my experience, up to 90% of SQL performance issues are related to skew. But this article is not about skew. Sometimes a slight change is enough to produce miracles. In this article, I show the possible impact of wrongly

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Long texts like descriptions are often stored in columns of data type VARCHAR(); if the column is defined as a character set LATIN, we can store up to 64000 characters. If specified as character set UNICODE, we can store up to 32000 characters. The more characters are stored in a VARCHAR column, the fewer rows

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Suppose you work in a well-organized environment where diligence and discipline prevail and significant effort is put into designing things right, in the beginning. In that case, the following post might seem outlandish to you. Else, read on. In a more “experimental” table design landscape, you will soon come across inconsistencies between column names, Teradata

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