導讀:1建站知識Oracle row_number() over()解析函數高效實現分頁，需要的朋友可以參考下。如何seo優化推廣網站網站建設多少錢。

復制代碼 代碼如下:

create table T_NEWS ( ID NUMBER, N_TYPE VARCHAR2(20), N_TITLE VARCHAR2(30), N_COUNT NUMBER ) prompt Disabling triggers for T_NEWS... alter table T_NEWS disable all triggers; prompt Loading T_NEWS... insert into T_NEWS (ID, N_TYPE, N_TITLE, N_COUNT) values (1, 'IT', '愛it1', 100); insert into T_NEWS (ID, N網站seo優化課程_TYPE, N_TITLE, N_COUNT) values (2, '體育', '愛體育1', 10); insert into T_NEWS (ID, N_TYPE, N_TITLE, N_COUNT) values (3, '體育', '愛體育2', 30); insert into T_NEWS (ID, N_TYPE, N_TITLE, N_COUNT) values (4, 'IT', '愛it2', 300); insert into T_NEWS (ID, N_TYPE, N_TITLE, N_COUNT) values (5, 'IT', '愛it3', 200); insert into T_NEWS (ID, N_TYPE, N_TITLE, N_COUNT) values (6, '體育', '愛體育3', 20); insert into T_NEWS (ID, N_TYPE, N_TITLE, N_COUNT) values (7, '體育', '愛體育4', 60); commit;

第一步：我先用rownum --分頁 row_number，不是rownum --根據n_count從大到小排列，每頁3條 SELECT ROWNUM r,t.* FROM t_news t WHERE ROWNUM<=3 ORDER BY t.n_count DESC --問題：為什么order by以后，行號是亂的？ SELECT ROWNUM r,t.* FROM t_news t --原因：先分配了行號，再根據n_count排序 --所以必須排序，再生成行號 SELECT ROWNUM r,t.* FROM ( 百度seo網站優化SELECT t.* FROM t_n建設網站公司ews t ORDER BY t.n_count DESC ) t --分頁 --err SELECT ROWNUM r,t.* FROM ( SELECT t.* FROM t_news t ORDER BY t.n_count DESC ) t WHERE r between 1 AND 3 --第1頁 SELECT ROWNUM r,t.* FROM ( SELECT t.* FROM t_news t ORDER BY t.n_count DESC ) t WHERE ROWNUM between 1 AND 3 --第2頁 SELECT ROWNUM r,t.* FROM ( SELECT t.* FROM t_news t ORDER BY t.n_count DESC ) t WHERE ROWNUM between 4 AND 6 --error: ROWNUM必須從1開始！ SELECT k.* FROM ( SELECT ROWNUM r,t.* FROM ( SELECT t.* FROM t_news t ORDER BY t.n_count DESC ) t ) k WHERE r BETWEEN 4 AND 6 --麻煩，效率低！ *****第二步:我用row_number() over()函數 select t2.* from (select t.*,row_number()over(order by t.n_count desc) orderNumber from t_news t order by t.n_count desc)t2 where orderNumber between 1and 3; *****************************************************************************************************************************************88 SELECT * FROM ( SELECT t.*,row_number() over(ORDER BY n_count DESC) r FROM t_news t ORDER BY t.n_count DESC ) t WHERE r BETWEEN 4 AND 6 --通用語法： 解析函數() over(partition by 字段 order by 字段)相關如何seo優化推廣網站網站建設多少錢。

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