LOB segment size

We can use below steps to claim space from LOB segments.

Get list of LOBs:

select owner,segment_name,segment_type,bytes/1024/1024/1024 as "Size_GB" from dba_segments where segment_name='<table_name>' and owner='<table_owner>';

Get List LOB Columns:

select owner,table_name,column_name from dba_lobs where owner='<owner_name>' and segment_name='<lob_segment_name>';

LOBs Size:

select sum(dbms_lob.getlength(<lob_column_name>)) from <table_owner>.<table_name>;