What is Teradata Query Rewriting? Teradata query rewriting is part of the Teradata optimization process. The optimizer replaces your query with a better version, which is assumed to be less resource-intense and, hopefully, faster. Of course, both queries have to deliver the same result set.  To achieve better performance, Teradata utilizes several optimization strategies. We will

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What is Teradata TPump? TPump stands for Teradata Parallel Data Pump. Teradata TPump does not move data in large blocks like Fastload or Multiload. Instead, it loads one row at a time, using row hash locks. Using row hash locks allows TPump to do many concurrent INSERTs and UPDATEs on a table. Teradata TPump is

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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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For indexed columns (PI, USI, NUSI) without statistics, Teradata calculates them at runtime. However, these statistics only contain a few key figures, such as the table cardinality and distinct values. This process is called dynamic AMP sampling or earlier also dynamic AMP sampling. Dynamic AMP samples are stored in the table header of each AMPs

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Quick Navigation 1. Complete and up-to-date Statistics2. Teradata Primary Index Choice3. Teradata SQL Tuning with Indexing & Partitioning4. Query Rewriting5. Teradata SQL Tuning with Real-Time Monitoring6. Comparison of Resource Usage 1. Complete and up-to-date Statistics Teradata SQL Tuning begins by providing the optimizer with the statistics it needs. This must always be done as a

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