Some SQL Statements - For Day to Day tasks

1) To grep & Drop user objects before Import
select 'drop 'object_type' 'object_namedecode(object_type,'TABLE','
cascade constraints;',';')
from user_objects
where object_type!='INDEX'/
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PCT_FREE, PCT_USED
SQL> select TABLE_NAME, PCT_FREE, PCT_USED, EMPTY_BLOCKS, CHAIN_CNT from dba_tables
2 where CHAIN_CNT > 0;
TABLE_NAME PCT_FREE PCT_USED EMPTY_BLOCKS CHAIN_CNT
------------------------------ ---------- ---------- ------------ ----------
BBN_MAS_LIQ_DET_TSY_TMP 10 40 1977 392
ORD_LEDGER 10 40 1982 6609
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SQL> select object_name,object_type from user_objects where status='INVALID';
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