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Data Types & Character Sets

A collection of 35 issues

The Pitfalls of Teradata SELECT * Queries

Introduction In a row-oriented database engine like Teradata, data is organized and stored in units called data blocks. Each data block features a fixed header and accommodates multiple rows. Every row consists of a record header followed by its corresponding columns. When a database retrieves and stores a data block

Maximizing Performance and Space Savings: Teradata Compression Techniques

Introduction to Teradata Compression Note: Teradata Block Level Compression is now permanently enabled and cannot be turned off. Nonetheless, this article remains useful for current Teradata systems utilizing block-level compression. It demonstrates the continued advantages of multi-value compression (Teradata MVC). With Teradata's introduction of block-level compression, the utilization

Teradata strtok_split_to_table, CSVLD, Unpack: Column Splitting in Teradata

Splitting column content can be a challenging task. Teradata provides multiple methods to achieve this, each with unique pros and cons. In this article, we will examine these techniques in detail. To begin, we will generate a table containing sufficient random data to assess every option's efficiency and

How the Number of Rows per Data Block Affects Teradata NUSI Selectivity: A Case Study

Teradata NUSI Selectivity and Data-Block Density The goal of this article is to show how the number of rows per base-table data block impacts the selectivity threshold for Non-Unique Secondary Indexes (NUSI) in Teradata. Understanding this correlation is critical when analyzing query plans and tuning indexing strategies. The number of

Teradata Data Type Considerations

Mastering Teradata Performance Tuning

The Art of Teradata Performance Tuning As a Teradata Performance Tuner, technical expertise and experience are essential, occasionally accompanied by fortuitous circumstances. I'll demonstrate the remarkable outcomes that can be attained by rephrasing a query using this example. Assuming this scenario: Want more practical data engineering analysis like

Teradata Set Operators: Understanding UNION vs. UNION ALL for Peak Performance Optimization

In this article, we will delve into the world of Teradata set operators, exploring their functionality, applications for attaining peak performance, and the optimization techniques employed by Teradata. Teradata UNION vs. UNION ALL What sets UNION apart from UNION ALL in Teradata? The Teradata UNION operator combines the results of

Loading Data into Teradata using Python and Fastload

This article assumes prior basic knowledge of Python and demonstrates the easy process of loading data using Python and the Teradata SQL Driver for Python with Fastload. If you are using Windows, we recommend using WinPython if you don't have Python installed yet. Because a Jupyter Notebook is

The Teradata Recursive Query for Performance Tuning