Oct
10

ROLLUP Function with Example

rollup_function

Guest Post  Author – Saurabh Gupta   In this post we will go through ROLLUP function which is one of the Extended grouping function. ROLLUP is used to aggregate data along all the levels of hierarchy within a single dimension. For example –  In time dimension data can be aggregated along different levels like day, week, month and …

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May
21

Teradata No Primary Index Tables

NOPI

What are No Primary Index tables ? Starting with Teradata Release 13, tables can be defined without having a primary index. As we all know, the primary index is the main idea behind an evenly data distribution on a Teradata system. By design, the primary index ensures that a Teradata system is unconditionally scalable. Hence, …

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Jan
17

Teradata 14 Certification

TD_CertLogo_SQL_Spec

Teradata 14 is the latest certification track launched by teradata after Teradata 12 certification. Teradata 14 certification covers the following database – Teradata 13.0 Teradata 13.10 Teradata 14.0 The list of exams is as follows –   Exam Exam Title Testing Time TE0-141 Teradata 14 Basics exam 1 hour 30 minutes TE0-142 Teradata 14 SQL exam …

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Mar
21

Partition Primary Index – Advantage and Disadvantage

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Advantage of Partition Primary Index – Partitioned Primary Index is one of the unique features of Teradata, which is used for distribution of rows based on different partitions so that they can be retrieved much faster than any other conventional approach. Maximum partitions allowed by Teradata – 65,535 It also reduces the overhead of scanning the complete …

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Feb
25

Partition Primary Index – Basics

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Partitioned primary index or PPI is used for physically splitting the table into a series of subtables. With the proper use of Partition primary Index we can save queries from time consuming full table scan. Instead of scanning full table, only one particular partition is accessed. Follow the example below to get the insight of PPI – …

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Jan
17

Compression in Teradata

compression

What is Compression in Teradata Compression is the feature of Teradata which helps to reduce the disk storage. It is useful in reducing the disk space required by FIXED LENGTH columns or NULLS. It is a loss less compression so no data will be lost in it. We can do compression on the following data …

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