AI is making everything easier to Oracle DBAs. Most of DBAs are familiar about shrink or reclaiming scape where balancing data growth with resource constraints is an ongoing challenge. In a recent discussion, one DBA highlighted a common predicament. Upon querying the database, they discovered a bigfile tablespaces supposedly utilizing only 140GB out of 2TB. To management, this signaled ample free space and a potential opportunity to reclaim and optimize storage rather than invest in additional disks.

Despite the reported 85% free space, attempts to shrink the bigfile tablespace down to accommodate the actual 140 GB of data hit a snag. Why? The data wasn’t neatly packed at the beginning of the file but scattered throughout, with the last allocated block far from the start. This phenomenon, known as fragmentation, poses a significant hurdle to resizing operations. For Oracle DBAs, dealing with such scenarios typically involves meticulous maneuvers like alter table move or resorting to export-import methods, both potentially involving downtime. Even advancements like online operations in newer Oracle versions come with their own set of constraints, such as handling long columns or specific data types.

Using Oracle Database 23 AI

Oracle Database 23 AI promises to revolutionize disk space management with innovations like DBMS_SPACE.TABLESPACE_SHRINK. This feature simplifies the reclaiming of unused space within tablespaces, offering DBAs a powerful tool to optimize storage without resorting to traditional, time-consuming methods.

Analyze Tablespace: 
 set serveroutput on
execute dbms_space.shrink_tablespace('BIGFILE_TABLESPACE_NAME', shrink_mode => dbms_space.ts_mode_analyze);

Shrink Tablespace
set serveroutput on
execute dbms_space.shrink_tablespace('BIGFILE_TABLESPACE_NAME');

NOTE: THIS OPERATION MIGHT TAKES LONGER TIME BETTER YOU USE nohup or screen commands .