Detecting Overlapping Time Periods with Teradata OVERLAPS Command: A Simple Syntax Guide
Learn how to use the Teradata OVERLAPS command to detect overlapping time periods with this example query. Caution: minimum overlap required.
SQL Tuning
Optimizing Queries with LIKE Operator in Teradata
Learn how to optimize LIKE operator queries in Teradata to avoid full table scans and improve performance. Read on for expert tips and tricks.
Enhancing Your Teradata Vantage Design with Teradata Historisation: A Comprehensive Method
Situation and Setup of a Historisation in Teradata Vantage Imagine that the time has come to improve your physical data model. Flawed or obsolete Teradata Vantage historisation design decisions need to be corrected. You are asked to separate tables of the same entity with different attributes. We do not question why there are separate tables …
Two Methods for Generating Number Ranges in Teradata
Method 1, avoiding any helper tables or functions which are only available in new releases of Teradata: Method 2, with helper tables and XMLAGG: Both methods deliver the string “1,2,3,4,5,6,7,8,9,10”. Which process do you believe is using fewer Disk IOs and CPU resources?
Why Teradata’s LIKE operator behaves differently for CHAR and VARCHAR columns
Have you observed the different behavior of the Teradata LIKE operator when applied to a CHAR or VARCHAR data type column? Consider the following table as an illustration: Creating a table: To illustrate, we will add a single row. We will run the SQL statement for the column with the VARCHAR data type. Next, we …
Advanced GROUPING Methods in Teradata SQL: GROUP BY GROUPING SETS, ROLLUP, and CUBE
Teradata SQL and Advanced GROUPING Functions The advanced GROUPING functions will be demonstrated through the following example. The foundation of this demonstration is a table consisting of the flight count for each aircraft and date: CREATE MULTISET TABLE Flights ( PLANE AS BIGINT NOT NULL, FLIGHTDATE AS DATE NOT NULL, NR_FLIGHTS INTEGER NOT NULL ) …
How to Find ASCII Code of a Character Using Teradata SQL
This course focuses on Teradata indexing techniques. In this two-hour video, you will learn about Teradata’s architecture and Full Table Scans, different types of Primary Index Access such as UPI and NUPI, diverse Secondary Index Access including USI and NUSI, and Join Indexes. You will gain the comprehensive knowledge required to create an ideal indexing …
Efficient Teradata Date Calculations Avoiding INTEGER Values
Learn how Teradata stores dates internally as INTEGER values and how to efficiently calculate dates after 1900-01-01 using a simple formula. Get more useful Teradata date calculations in this article.
Teradata DDL Best Practice: Use DELETE Instead of DROP for Efficiency and Resource Management
Learn why you should opt for DELETE instead of DROP when it comes to Teradata DDL. Avoid locking dictionary tables and conserve resources.
Benefits of Organizing Stored Procedures into Chapters and Steps
I made organizing Stored Procedures into Chapters and Steps a principle. These separation points are marked by comments and variables used in performance and result logging. A step refers to a technical or conceptual task that cannot be further divided without losing the abstraction of Stored Procedures or the main task. Examples of a step …