Tag Archives: Oracle

Oracle Bitmap Index

Common usage of Bitmap Indexes is a data warehousing environment. This implies large amounts of data, high level of ad-hoc queries but a low level of concurrent DLM transactions. Why to use? reduced response time reduced storage requirements compared to other … Continue reading

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Oracle Reverse Index

This is one of the least used Oracle indexes I’ve encountered in a data-warehousing environment. However, a very good instrument in performance problems on OLTPs. To understand a reverse key index, we must first look at the regular b-tree index … Continue reading

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Cursor Loop Updates

I’m writing this topic mostly for database developer coming from the programming world. I have seen various procedural units which use the for syntax to run updates on base tables. Scenarios like the one bellow. FOR update SQL: for i … Continue reading

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Oracle: Partition by List Sub-Partition by Range– Example

The following post will walk you trough an exercise of creating a partitioned table, using the list partitioning, with range sub-partitioning (explicit definition of partitions and sub-partitions naming), populating and testing the partition pruning. Please note I will also post … Continue reading

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Working with Large Data Volumes – Partitioning

As more and more the increase in information is getting visible to each database user, there comes a question on how are we to process these volumes in a Data Warehouse environment. One of the first answers provided by Oracle … Continue reading

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Oracle: Partition by Range– Example

The following post will walk you trough an exercise of creating a partitioned table, using the range partitioning (with auto define of partition names), populating and testing the partition pruning. Please note I will also post the scripts at each section so … Continue reading

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Oracle: Partition by List – Example

The following post will walk you trough an exercise of creating a partitioned table, using the list partitioning, populating and testing the partition pruning. Please note I will also post the scripts at the end of the post, so you … Continue reading

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