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3 Types of Temporal Tables in Teradata

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What is a Temporal Database Definition - Temporal – the ability to store all states of a given set of data (a database row), as part of the query select a point in time to reference the data. Examples: What was this account balance (share price, inventory level, asset value, etc) on this data? What data went into the calculation on 11/3/07, and what adjustments were made in 2008? On this historic data, what was the service level (contract status, customer value, insurance policy coverage) for said customer? Three Types of Temporal Tables 1. Valid Time tables When a fact is true in the modeled reality. User specified times. 2. Transaction time Tables When a fact is stored in the database. System maintained time, no user control. 3. Bitemporal Tables Both Transaction Time and Valid Time User defined Time User can add time period columns, and take advantage of the added temporal operators Database does not enforce any rules on user defined time columns. T

How to refresh Hadoop the best way in three minutes

How best You can use Teradata data mover

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Top advantages of Teradata data mover in data warehousing projects. An End-to-End Management Solution. Before going in detail you can refresh All You Need to Know About Teradata Architecture . You can also integrate data movement within your comprehensive ecosystem management and load jobs and automate.  Teradata Data Mover for your production execution needs.  That’s because the utility can be tightly integrated with Teradata Multi-System Manager for end-to-end management of changes to your environment.  The utility works with Teradata Multi System Manager to support these commands and status messages: Send event for the start of a job.  Send event for end of a job.  Send event for a job in progress.  And Teradata Data Mover can be integrated with load process to copy data to a second system.That means you can copy data from an EDW to a data mart as soon as the data are loaded into the EDW.  Teradata Data Mover also provides safeguards to force the direction of data m

Top features of Teradata data mover for large data transfer

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Teradata Data Mover Moving data from one system to another is a key part of your analytical ecosystem operation. Well-planed, monitored, and managed data movement is essential to effective operation of your overall ecosystem. Whether your goal is to complete a onetime copy of data from your enterprise data warehouse (EDW) to your test system or to regularly and continuously synchronize a dual system environment, you need confidence that the data will be in the right place at the right time while causing the smallest possible impact on the data warehouse’s mission of serving your business. The decision about the best way to copy data between Teradata systems depends on many factors, including the data model and indexes present, other workloads in your system, and additional load jobs underway. What you need is a solution that automates the data movement process, a solution that also accommodates the many situations found within your comprehensive analytical ecosystem. And th

New features in Teradata 14 (1 of 2)

Teradata 14.0 new features. It is columnar database New security features added Enhanced capability in workload and system management Compression Temporal tables TTU14.0 TTU 14 (Teradata tools and utilities) compatible with previous relaeses TASM(Teradata workload manager only supports with version 12 Teradata  query director is not available in TU 14.0. It is replaced by Teradata unity TTU 14.0 now supports, Redhat 6X, Zo/s 1.12, Zos 1.13, AIX 7.1 and Solaris 11 Support for the following Os are dropped- HP-UX11.11, Redhat Linux Advaned server 3.0, Windows 2000, Linux SUSE9, Solaris 8 New Application program interfaces Teradata CLIV2-ODBC driver for Teradata- Teradata JDBC driver OLEDB provider for Teradata-Teradata pre processor 2, .Net provider for Teradata Support libraraies-ICU-Tera GSS End user utilities- Teradata SQL assist - BTEQ Load and Unload utilities- Teradata parallel transporter Stand alone utilities- Fast load, Fast export, MultiLoad and Tpum

Top Teradata Interview Questions and Answers (2 of 7)

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#Top Teradata Interview Questions and Answers: The teradata interview questions of second set. What is the usage of Fallback? A) When a table is fallback protected the rows are duplicated on other AMPs. Fallback is similar to mirroring, but different. The similarities is that both provide a duplicate copy, but the difference is that Fallback places copies of its rows on multiple AMPs so if a failure occurs Teradata can use the parallelism to help the failed AMP. Teradata+Interview +Questions-Part-1 How many primary keys we will apply on a table? A) Only one How does rows store in Teradata? A) It spreads the rows across all AMPs Tell me the types of Indexes? A) PI - Primary index NoPI-No primary index UPI-Unique primary index NUPI-Non unique primary index USI-Unique secondary index NUSI-Non unique secondary index Difference between UPI and NUPI and the situation where exactly? We will use these? Teradata indexes The role of SI in teradata and explain