If you have spent any amount of time working with Teradata, you know that the Primary Index is one of the most important design decisions you make. It determines how data is distributed across AMPs and whether your joins are fast or slow. Choosing the wrong Primary Index is one of the most common causes …
Introduction to Teradata Performance and NOT NULL Welcome to our latest Teradata performance blog post, a series designed to provide valuable insights into SQL queries. This article spotlights ‘NOT NULL’. To delve deeper into ‘NOT IN’, it is crucial to comprehend a frequently neglected SQL database design principle: properly defining columns that cannot hold NULL …
Learn how to optimize your Teradata SQL performance by leveraging secondary indexes! Avoid full table scans by bypassing the COALESCE function in the WHERE clause.
Learn how to overcome the hurdle of using Teradata Identity columns with Volatile Tables. Discover a workaround using the ‘CREATE TABLE AS’ statement.
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 in the cache, it accesses …
The Teradata flavor of SQL is still, in principle, a declarative language. Hence, there can be multiple ways to describe an SQL query and achieve the same result. While the answer is the same, Teradata may use a completely different execution plan based on how the query is expressed. One approach is investing in heavy …
What is the Teradata TD_WhichMax Function? Teradata releases new SQL features with each update, providing enhanced functionality and improved performance with reduced resource usage. We will examine the Teradata TD_WhichMax and TD_WhichMin functions and explore their potential benefits. These functions retrieve the minimum or maximum value of a column and are commonly utilized in SQL …
In a previous article, Roland explained how to use recursion to build a data range without touching a physical table. This time, we explore an alternative approach that avoids recursion at the expense of single-AMP, single-row access. We can use this approach to build both a wide date range as well as a narrow one. We …
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 resource utilization. The Teradata “CSVLD” Function This …
Have you ever experienced extended waiting times for a table comparison to yield results? Have you ever been compelled to halt and defer quality checks on sizable tables owing to excessive resource utilization during a previous attempt? What if you possessed a straightforward screening test indicating which tables require further examination from a huge array …
Expert network for enterprise data platforms. Senior consultants, project teams built for your challenge — across Teradata, Snowflake, Databricks, and more.
📍Vienna, Austria & Jacksonville, Florida
Join 4,000+ data professionals.
Weekly insights on Teradata, Snowflake & data architecture.