After truncation space not reclaiming

Question

HI,
During our health check we found one of the tables in our database occupying more than 11 GB of space. We got approval from APP team to truncate the table.
And i truncated accordingly.
But after truncation also the table is still showing the same size.
I checked the record count. it's showing ZERO records.
Could you please let me know why my database behaving like this?
Before tables truncation
*================*
select OWNER,SEGMENT_NAME,SEGMENT_TYPE,BYTES/1024/1024/1024 FROM dba_segments WHERE TABLESPACE_NAME='WEBMDATA' and SEGMENT_TYPE='TABLE' and bytes/1024/1024/1024 > 1;
OWNER SEGMENT_NAME SEGMENT_TYPE BYTES/1024/1024/1024
PRISMA_WMISCORE_OWNER1 WMERROR TABLE 11.2998047
1 row selected.
SQL> truncate table PRISMA_WMISCORE_OWNER1.WMERROR;
Table truncated.
SQL> select count(*) from PRISMA_WMISCORE_OWNER1.WMERROR;
COUNT(*)
0
1 row selected.
After table truncation
*==============*
SQL> select OWNER,SEGMENT_NAME,SEGMENT_TYPE,BYTES/1024/1024/1024 FROM dba_segments WHERE TABLESPACE_NAME='WEBMDATA' and SEGMENT_TYPE='TABLE' and bytes/1024/1024/1024 > 1;
OWNER SEGMENT_NAME SEGMENT_TYPE BYTES/1024/1024/1024
PRISMA_WMISCORE_OWNER1 WMERROR TABLE 11.2998047
1 row selected.
Please help me..
Thank you..

Answer 1

HI,
Thanks for the response.
Even after stats gathering also its showing the same size..
SQL> select table_name,last_analyzed FROM DBA_TABLES WHERE table_name='WMERROR' AND OWNER='PRISMA_WMISCORE_OWNER1';
TABLE_NAME LAST_ANAL
WMERROR 17-AUG-12
SQL> select OWNER,SEGMENT_NAME,SEGMENT_TYPE,BYTES/1024/1024/1024 FROM dba_segments WHERE TABLESPACE_NAME='WEBMDATA' and SEGMENT_TYPE='TABLE' and bytes/1024/1024/1024 > 1;
OWNER SEGMENT_NAME SEGMENT_TYPE BYTES/1024/1024/1024
PRISMA_WMISCORE_OWNER1 WMERROR TABLE 11.2998047
1 row selected.