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【DM版本】:
【操作系统】：
【CPU】:
【问题描述】*：```language
SQL> 2 3 4 5 6 7 8 9 10 11 12 13 14 15

LINEID column_id owner table_name column_name data_type data_length nullable

1 1 WWMH TABLE_1 COLUMN_1 TIMESTAMP 8 Y

used time: 8.604(ms). Execute id is 709.
SQL> alter table wwmh.table_1 modify COLUMN_1 TIMESTAMP(6);
executed successfully
used time: 965.014(ms). Execute id is 710.
SQL> select
t.column_id,
t.owner,
t.table_name ,
t.column_name ,
t.data_type ,
t.data_length ,
t.nullable
from
all_tab_columns t
where t.owner='WWMH' and t.data_type='timestamp' and t.table_name='TABLE_1'
order by
t.column_id ; 2 3 4 5 6 7 8 9 10 11 12 13

LINEID column_id owner table_name column_name data_type data_length nullable

1 1 WWMH TABLE_1 COLUMN_1 TIMESTAMP 8 Y