What is the Teradata Primary Index? The Teradata primary index is a mechanism that decides where each data row is physically located. It may be based on a single column or multiple columns. The values of the primary index columns may be unique or non-unique. Don’t confuse the primary index with the primary key of

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Teradata Access Paths 1. FULL TABLE SCAN2. UNIQUE PRIMARY INDEX (UPI)3. NON-UNIQUE PRIMARY INDEX (NUPI)4. UNIQUE SECONDARY INDEX (USI)5. NON-UNIQUE SECONDARY INDEX (NUSI)6. SINGLE-TABLE JOIN INDEX7. MULTI-TABLE JOIN INDEX8. SPARSE JOIN INDEX The optimizer has various access paths to choose from when creating the execution plan. Each of these access paths has certain advantages and

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Teradata Query Parallelism If we run a query on a Teradata system, it runs in parallel in every step, no matter if it is a join, sorting, aggregation step, etc. The great advantage is that this applies to each step of the query process. That’s what makes Teradata unique. The big advantage Teradata has over

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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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The Teradata Architecture Video Course. This video will give you an overview about the Teradata Shared Nothing Architecture. We will show you how Teradata distributes data evenly across its parallel units and how the different components interact with each other.

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This article assumes that you are already familiar with the general architecture of a Teradata System. As you should already know, the AMPs are responsible for doing the work on a Teradata System. Depending on the size of the system, you will have hundreds of AMPs, each one being in charge of handling the rows

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