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For partitioned tables, you can optionally identify the tablespace that is to store each partition.
Ensure that you have the appropriate privileges and quota on any tablespaces that you use.
Either the DBA or the applications developer, or both working jointly, can be responsible for the actual creation of the tables, depending upon the practices for a site.
Working with the application developer, consider the following guidelines when designing tables: Before creating a table, you should also determine whether to use integrity constraints.
In general, the relative performance improvement of specifying Compression saves disk space, reduces memory use in the database buffer cache, and can significantly speed query execution during reads.
Compression has a cost in CPU overhead for data loading and DML.
Unlike an ordinary (heap-organized) table, data for an index-organized table is stored in a B-tree index structure in a primary key sorted manner.
Besides storing the primary key column values of an index-organized table row, each index entry in the B-tree stores the nonkey column values as well.
It is useful in decision support systems (DSS), online transaction processing (OLTP) systems, and archival systems.A cluster is a group of tables that share the same data blocks because they share common columns and are often used together.Clusters and clustered tables are discussed in Managing Clusters.Index-organized tables are discussed in Partitioned tables enable your data to be broken down into smaller, more manageable pieces called partitions, or even subpartitions.Each partition can have separate physical attributes, such as compression enabled or disabled, type of compression, physical storage settings, and tablespace, thus providing a structure that can be better tuned for availability and performance.