Day-6 : Storage management(Extent/block/segment management)

What is data block?
Oracle database's data is stored in data blocks. One data block corresponds to a specific number of bytes of physical database space on disk.

How to define data block size?
A data block size is specified for each Oracle database when the database is created. A database users and allocated free database space in Oracle data blocks. Block size is specified in init.ora file and cannot be changed latter.

What is row chaining?
In circumstances, all of the data for a row in a table may not be able to fit in the same data block. When this occurs, the data for the row is stored in a chain of data block (one or more) reserved for that segment.

What is an extent?
An extent is a specific number of contiguous data blocks, obtained in a single allocation and used to store a specific type of information.

What is a segment?
A segment is a set of extents allocated for a certain logical structure.

What are the different types of segments?
Data segment, index segment, rollback segment and temporary segment.

What is an index segment?
Each index has an index segment that stores all of its data.

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ORA-600 [kwqitnmphe:ltbagi], [1], [0] reported in the alert log file.

ORA-00600 [kwqitnmphe:ltbagi] Cause: This issue arises in 12.1.0.2. The error occurs because there are still Historical Messages without...