oracle 語句

1、創建索引

CREATE INDEX INDEX_NAME ON TABLENAME (COL_NAME) NOLOGGING PARALLEL 4;

2、去重複，然後取一條數據

<1> select * from table where rowid=any(select max(rowid) from table groupby cola)

<2> select * from table where rowid in (select max(rowid) from table groupby cola)