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alter table tb_test modify permile number(5,2);
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alter table tb_test add permile_temp number(5,2)
update tb_test set permile_temp=permile;
alter table drop column permile;
alter table test rename column permile_temp to permile;
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alter table tb_test add permile_temp number;
Add/modify columns
alter table tb_test modify PERMILE null;
update tb_test set permile_temp=permile,permile=null;
commit;
alter table tb_test modify permile number(5,2);
update tb_test set permile=permile_temp,permile_temp=null;
commit;
alter table tb_test drop column permile_temp;
alter table tb_test modify PERMILE not null;
select * from tb_test ;
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CREATE TABLE example(
ID Number(4) NOT NULL PRIMARY KEY,
NAME VARCHA ......
SQL> select * from emp where sal=800;
EMPNO ENAME JOB MGR HIREDATE SAL COMM DEPTNO
----- ---------- --------- ----- ----------- ----- ......
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SQL> select * from emp where sal>2999;
EMPNO ENAME JOB MGR HIREDATE ......
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select a, b, c, versions_xid, versions_starttime, versions_endtime,
versions_startscn,versions_endscn,versions_operation
from test versions between scn 339493 and 339635
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from te ......