SELECT COLUMN_NAME, DATA_TYPE||'('||DATA_LENGTH||')'FROM USER_TAB_COLUMNS
where table_name=upper('表名') and column_name=upper('字段名')
ORDER BY NULLABLE
where table_name=upper('表名') and column_name=upper('字段名')
ORDER BY NULLABLE
create table A as select * from b;这条语句怎样才能不把数据也创建进来呢?