To explicitly specify where the LOB will reside if its size is 4000 bytes or less, use the disable
storage in row or enable storage in row clause in the LOB storage clause of the create table
statement. If a LOB is stored inline, and its value starts out with a size less than 4000 bytes, it will
migrate to out of line. If an out of line LOB??™s size becomes less than 4000 bytes, it stays out of line.
Sizing Partitions
You can create multiple partitions of a table. In a partitioned table, multiple separate physical
partitions constitute the table. For example, a SALES table may have four partitions: SALES_NORTH,
SALES_SOUTH, SALES_EAST, and SALES_WEST. You should size each of those partitions using
the table-sizing methods described earlier in this chapter. You should size the partition indexes
using the index-sizing methods shown earlier in this chapter.
Using Temporary Tables
You can create temporary tables to hold temporary data during your application processing.
The table??™s data can be specific to a transaction or maintained throughout a user??™s session.
When the transaction or session completes, the data is truncated from the table.
150 Oracle Database 11g DBA Handbook
To create a temporary table, use the create global temporary table command. To automatically
delete the rows at the end of the transaction, specify on commit delete rows, as shown here:
create global temporary table MY_TEMP_TABLE
(Name VARCHAR2(25),
Street VARCHAR2(25),
City VARCHAR2(25))
on commit delete rows;
You can then insert rows into MY_TEMP_TABLE during your application processing.
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