When you
commit, Oracle will truncate MY_TEMP_TABLE. To keep the rows for the duration of your session,
specify on commit preserve rows instead.
From the DBA perspective, you need to know if your application developers are using this
feature. If they are, you need to account for the space required by their temporary tables during
their processing. Temporary tables are commonly used to improve processing speeds of complex
transactions, so you may need to balance the performance benefit against the space costs. You
can create indexes on temporary tables to further improve processing performance, again at the
cost of increased space usage.
NOTE
Temporary tables and their indexes do not allocate any space until
the first insert into them occurs. When they are no longer in use, their
space is deallocated. In addition, if you are using PGA_AGGREGATE
TARGET, Oracle will try to create the tables in memory and will only
write them to temporary space if necessary.
Supporting Tables Based on Abstract Datatypes
User-defined datatypes, also known as abstract datatypes, are a critical part of object-relational
database applications. Every abstract datatype has related constructor methods used by developers
to manipulate data in tables. Abstract datatypes define the structure of data??”for example, an
ADDRESS_TY datatype may contain attributes for address data, along with methods for manipulating
that data. When you create the ADDRESS_TY datatype, Oracle will automatically create a constructor
method called ADDRESS_TY.
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