數(shù)據(jù)庫實驗報告二-資料下載頁
2025-08-04 02:01本頁面
【正文】 @number = 200000 WHILE @number 0 BEGIN INSERT ( MsId, Title, TitleBak, Summary, SummaryImageUrl, Tag, ArticleChannel_Id, ArticleCategory_Id, IsApproved, Creator_Id, CreatedDateTime, ModifiedDateTime, ViewCount, ReplyCount, DiggCount, FavoriteCount, LastReplyUser_Id, LastReplyDateTime, RightType, IsDisplayContent, IsSensitive, Source ) VALUES ( @number, 39。Title39。+cast(@number AS VARCHAR(20)), 39。TitleBak39。+cast(@number AS VARCHAR(20)), 39。Summary39。+cast(@number AS VARCHAR(20)), 39。SummaryImageUrl39。+cast(@number AS VARCHAR(20)), 39。Tag39。+cast(@number AS VARCHAR(20)), 1, 2, 0, @number, GETDATE(), GETDATE(), 100, 29, 123, 12, @number, GETDATE(), 1, 0, 0, 2 ) SET @number=@number1END沒建立索引前，利用語句，查詢開銷，看執(zhí)行計劃WITH TEMP AS(SELECT ROW_NUMBER() OVER (ORDER BY CreatedDateTime) AS ROW,CreatedDateTime,ViewCountFROM ArticleWHERE Creator_Id=199996 )SELECT *FROM TEMPWHERE ROW BETWEEN 1 AND 5建立索引之后，再執(zhí)行一次查詢,執(zhí)行計劃如下：細(xì)節(jié)內(nèi)容如下：可以看到，利用索引查詢，開銷明顯減少。（參考文獻(xiàn)與博客：）二、實驗反思 利用索引查詢數(shù)據(jù)，效率明顯提高；觸發(fā)器可以實現(xiàn)表或者視圖中難以刪除、更改的數(shù)據(jù)
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