We need to figure out let us say in userspace1,if it is full what tables and indexes occupies all the spaces ..

Any help will be appreciated...

To find the size of a table use the following query -

SELECT T1.TABLENAME,
T1.FPAGES*T2.PAGESIZE TABLESIZE_BYTES
FROM SYSCAT.TABLES T1,
SYSCAT.TABLESPACES T2
WHERE T1.TBSPACE = T2.TBSPACE
AND T1.TABNAME 'YOUR_TABLE_NAME' ;

To list all tables in a tablespace (largest table first), use the following query

SELECT T1.TABLENAME,
T1.FPAGES*T2.PAGESIZE TABLESIZE_BYTES
FROM SYSCAT.TABLES T1,
SYSCAT.TABLESPACES T2
WHERE T1.TBSPACE = T2.TBSPACE
AND T2.TBSPACE = 'YOUR_TABLESPACE_NAME'
ORDER BY 2 DESC ;

Note that there some people might insist on using "NPAGES" instead of "FPAGES" in the above queries, but I leave the choice upto you !

There is no easy way to get the "size" of an index. However, you can do relative sizing by counting the "leaf pages" as follows -

SELECT T1.INDEXNAME,
T1****EAF*T3.PAGESIZE INDEX_LEAF_SUM_BYTES
FROM SYSCAT.INDEXES T1,
SYSCAT.TABLES T2,
SYSCAT.TABLESPACES T3
WHERE T1.TABNAME = T2.TABNAME
AND T1.TABSCHEMA = T2.TABSCHEMA
AND T2.INDEX_TBSPACE = T3.TABSPACE
AND T3.TABSPACE = 'YOUR_TABLESPACE_NAME'
ORDER BY 2 DESC ;