In a SQL database query, a correlated subquery (also known as a synchronized subquery) is a subquery (a query nested inside another query) that uses values from the outer query. Because…
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Author: Bulent Soylu
Partitioning Large Tables
About Table Partitioning Partitioning does not change the physical distribution of table data across the segments. Table distribution is physical: Greenplum Database physically divides partitioned…
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What is the difference between Oracle Client 19c and Oracle Client Home 19c?
When I tried to download and install Oracle client 19c, it was my surprise that there are two different versions. See the following information from…
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PostgreSQL EXPLAIN Explained
When a SQL statement is sent to a PostgreSQL server for execution, Postgres will decipher various parts of the query and define an execution plan…
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TOAST compression and toast_tuple_target
What is the TOAST ? Have you ever wondered how Postgres stores rows that exceed the size of a block? As a reminder, the default…
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LZ4 TOAST compression in PostgreSQL 14
Background In PostgreSQL, a page is the basic unit to store data, and the size of each page is 8 kB by default. Basically, data in one…
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Postgres Locks
Table Locks If you ask me what a table lock three years ago I would say its a lock you obtain on a table so…
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How to measure performance of PostgreSQL Database Server(s)?
The benchmark test is designed to evaluate and compare the performance of different configurations, topologies, systems and components. For this purpose I will use the…
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Speeding Up “min” and “max” functions in postgresql
Indexes are a perfect tool to finding a certain value or some kind of range in a table. It is possible to speed up a…
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Enabling High Performance Data Streaming with the Memoptimized Rowstore
The Memoptimized Rowstore enables high performance data streaming for applications, such as Internet of Things (IoT). About the Memoptimized Rowstore The Memoptimized Rowstore enables high…
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