通過/ distinct查詢firebird慢速順序

Question

我對Firebird中的查詢速度有疑問。 緩慢是在排序和清晰。

如果我在MySQL中嘗試查詢，那么他會快一秒。

Firebird - > 1,3s a 1,6s MySQL - > 0,3s a 0,4s

我們在Web服務器/網站上使用Firebird數據庫，因此速度很重要。

規格： - Firebird 2.5.1或2.5.2（SuperClassic）64位 - 2,13 Ghz（2個處理器） - RAM 4,00 GB

我能做什么？

我有以下表格：

================================================== ==

CREATE TABLE ARTICLE3_1
(
  IDARTICLE Integer NOT NULL,
  ITEMSTATUS Integer,
  ITEMENTRYDATE Integer,
  ITEMFILTER Integer,
  ARTIKELNUMMER Varchar(250),
  ARTIKELNAAM1 Varchar(250),
  ARTIKELNAAM2 Varchar(250),
  OMSCHRIJVING_DETAIL Blob sub_type 1,
  OMSCHRIJVING1 Varchar(250),
  OMSCHRIJVING2 Varchar(250),
  ARTIKELNR_LEVERANCIER Varchar(250),
  MERK Varchar(250),
  LEVERANCIER Varchar(250),
  EAN Varchar(250),
  LINKAANGROEP Varchar(250),
  LINKAANAANBIEDINGGROEP Varchar(250),
  LINKAANPOPULAIRGROEP Varchar(250),
  LINKAANART Varchar(250),
  ARTGRPNR Varchar(250),
  SUBGROEP Varchar(250),
  PRIJSPER Integer,
  VERKOOPPRIJS Float,
  ADVIESPRIJS Float,
  BTWPERC Float,
  ONLINE Varchar(250),
  TUSGROEPBIJLINK Varchar(250),
  AFBEELDINGKLEIN Varchar(250),
  AFBEELDINGMIDDEL Varchar(250),
  AFBEELDINGGROOT Varchar(250),
  ICECATLINK Varchar(250),
  LINKAANHOMEPAGEGROEP Varchar(250),
  LINKAANMIJNACCOUNTGROEP Varchar(250),
  SORTEER Varchar(250),
  AFBEELDING Varchar(100),
  FLASH Blob sub_type 1,
  EENHEID Varchar(250),
  ALTARTNR1 Varchar(250),
  ALTARTNR2 Varchar(250),
  BESTELLENPER Float,
  INFEED Varchar(250),
  GOOGLE_TAXONOMIE Varchar(250),
  FEED_TITEL Varchar(250),
  FEED_OMSCHRIJVING Blob sub_type 1,
  PRIMARY KEY (IDARTICLE)
);
CREATE INDEX IDX_ARTICLE3_1_2 ON ARTICLE3_1 (MERK);
CREATE INDEX IDX_ARTICLE3_1_3 ON ARTICLE3_1 (ARTIKELNUMMER);
CREATE INDEX IDX_ARTICLE3_1_4 ON ARTICLE3_1 (ARTIKELNR_LEVERANCIER);
CREATE INDEX IDX_ARTICLE3_1_5 ON ARTICLE3_1 (ALTARTNR2);
CREATE INDEX IDX_ARTICLE3_1_6 ON ARTICLE3_1 (ARTIKELNAAM1);
CREATE INDEX IDX_ARTICLE3_1_7 ON ARTICLE3_1 (EAN);

   CREATE TABLE TREE3
(
  IDLINK Integer NOT NULL,
  LINKTYPE Integer,
  IDITEM Integer,
  ITEMTYPE Integer,
  IDTARGETLINK Integer,
  NODEPOSITION Integer,
  NODELEVEL Integer,
  IDLAYOUTDATA Integer,
  IDTEMPLATE Integer,
  ACTIONDATE Integer,
  MARKET1 Integer,
  PRIMARY KEY (IDLINK)
);
CREATE INDEX IDX_TREE3_2 ON TREE3 (IDITEM);
CREATE INDEX IDX_TREE3_3 ON TREE3 (MARKET1);
CREATE INDEX ITREE13 ON TREE3 (IDTARGETLINK,NODEPOSITION);
CREATE INDEX ITREE53 ON TREE3 (IDITEM,ITEMTYPE);

====================================================

FireBird中的查詢：

SELECT FIRST 30 SKIP 0 distinct tr.IdLink, tr.IdTargetLink, tr.IdItem, tr.NodePosition
FROM Tree3 tr
inner join article3_1 art on art.idarticle = Tr.iditem
WHERE tr.ItemType = 2 AND tr.Market1 = 1
AND  ((art.IDARTICLE > 0) AND (  (LOWER(art.Artikelnummer) like '%a4 papier%' ) OR ( (LOWER(art.Artikelnummer) like 'a4' )
AND (LOWER(art.Artikelnummer) like 'papier'))  OR  (LOWER(art.Artikelnaam1) like '%a4 papier%' ) OR ( (LOWER(art.Artikelnaam1) like '%a4%' )
AND (LOWER(art.Artikelnaam1) like '%papier%'))  OR  (LOWER(art.Artikelnaam2) like '%a4 papier%' ) OR ( (LOWER(art.Artikelnaam2) like '%a4%' )
AND (LOWER(art.Artikelnaam2) like '%papier%'))  OR  (LOWER(art.Artikelnr_leverancier) like '%a4 papier%' ) OR ( (LOWER(art.Artikelnr_leverancier) like '%a4%' )
AND (LOWER(art.Artikelnr_leverancier) like '%papier%'))  OR  (LOWER(art.Merk) like '%a4 papier%' ) OR ( (LOWER(art.Merk) like '%a4%' )
AND (LOWER(art.Merk) like '%papier%'))  OR  (LOWER(art.EAN) like '%a4 papier%' ) OR ( (LOWER(art.EAN) like '%a4%' )
AND (LOWER(art.EAN) like '%papier%'))  OR  (LOWER(art.AltArtnr1) like '%a4 papier%' ) OR ( (LOWER(art.AltArtnr1) like '%a4%' )
AND (LOWER(art.AltArtnr1) like '%papier%'))  OR  (LOWER(art.AltArtnr2) like '%a4 papier%' ) OR ( (LOWER(art.AltArtnr2) like '%a4%' )
AND (LOWER(art.AltArtnr2) like '%papier%')) ))
AND tr.NODELEVEL =5  and tr.LINKTYPE <> 5
ORDER BY tr.NodePosition

MySQL中的查詢：

SELECT  distinct tr.IdLink, tr.IdTargetLink, tr.IdItem, tr.NodePosition
FROM Tree3 tr
inner join article3_1 art on art.idarticle = Tr.iditem
WHERE tr.ItemType = 2 AND tr.Market1 = 1
AND  ((art.IDARTICLE > 0) AND (  (LCASE(art.Artikelnummer) like '%a4 papier%' ) OR ( (LCASE(art.Artikelnummer) like 'a4' )
AND (LCASE(art.Artikelnummer) like 'papier'))  OR  (LCASE(art.Artikelnaam1) like '%a4 papier%' ) OR ( (LCASE(art.Artikelnaam1) like '%a4%' )
AND (LCASE(art.Artikelnaam1) like '%papier%'))  OR  (LCASE(art.Artikelnaam2) like '%a4 papier%' ) OR ( (LCASE(art.Artikelnaam2) like '%a4%' )
AND (LCASE(art.Artikelnaam2) like '%papier%'))  OR  (LCASE(art.Artikelnr_leverancier) like '%a4 papier%' ) OR ( (LCASE(art.Artikelnr_leverancier) like '%a4%' )
AND (LCASE(art.Artikelnr_leverancier) like '%papier%'))  OR  (LCASE(art.Merk) like '%a4 papier%' ) OR ( (LCASE(art.Merk) like '%a4%' )
AND (LCASE(art.Merk) like '%papier%'))  OR  (LCASE(art.EAN) like '%a4 papier%' ) OR ( (LCASE(art.EAN) like '%a4%' )
AND (LCASE(art.EAN) like '%papier%'))  OR  (LCASE(art.AltArtnr1) like '%a4 papier%' ) OR ( (LCASE(art.AltArtnr1) like '%a4%' )
AND (LCASE(art.AltArtnr1) like '%papier%'))  OR  (LCASE(art.AltArtnr2) like '%a4 papier%' ) OR ( (LCASE(art.AltArtnr2) like '%a4%' )
AND (LCASE(art.AltArtnr2) like '%papier%')) ))
AND tr.NODELEVEL =5  and tr.LINKTYPE <> 5
ORDER BY tr.NodePosition LIMIT 30;

================================================== ==

我有使用FlameRobin執行的查詢：

> Prepare time: 0.016s Field #01: TREE3.IDLINK Alias:IDLINK Type:INTEGER
> Field #02: TREE3.IDTARGETLINK Alias:IDTARGETLINK Type:INTEGER Field
> #03: TREE3.IDITEM Alias:IDITEM Type:INTEGER Field #04: TREE3.NODEPOSITION Alias:NODEPOSITION Type:INTEGER PLAN SORT (SORT
> (JOIN (TR INDEX (IDX_TREE3_2, IDX_TREE3_3), ART INDEX
> (RDB$PRIMARY2))))
> 
> 873424 fetches, 0 marks, 12892 reads, 0 writes. 0 inserts, 0 updates,
> 0 deletes, 380580 index, 0 seq. Delta memory: 1784 bytes. Total
> execution time: 1.311s

謝謝！

Answer 1

如果可以，Yip避免使用DISTINCT和LIKE，DISTINCT優化http://dev.mysql.com/doc/refman/5.0/en/distinct-optimization.html

嘗試使用group by而不是distinct來嵌套查詢。 我使用它來解決使用group by和order by時的問題。

select * from ({the rest of the query}) as some_table group by {my distinct column};

我也看不到你的表引擎，但MyIsam更適合全文搜索（而不是InnoDB）。 同樣值得看看Solr進行全文搜索。 設置一些學習曲線，但您可以索引mysql表，然后跨多個列執行部分匹配搜索。 隨着提升和令人敬畏的事情。

查看以下查詢是否具有任何性能優勢。

select * from (SELECT tr.IdLink, tr.IdTargetLink, tr.IdItem, tr.NodePosition
FROM Tree3 tr
inner join article3_1 art on art.idarticle = Tr.iditem
WHERE tr.ItemType = 2 AND tr.Market1 = 1
AND  ((art.IDARTICLE > 0) AND (  (LCASE(art.Artikelnummer) like '%a4 papier%' ) OR (
(LCASE(art.Artikelnummer) like 'a4' )
AND (LCASE(art.Artikelnummer) like 'papier'))  OR  (LCASE(art.Artikelnaam1) like '%a4 papier%' ) OR ( (LCASE(art.Artikelnaam1) like '%a4%' )
AND (LCASE(art.Artikelnaam1) like '%papier%'))  OR  (LCASE(art.Artikelnaam2) like '%a4 papier%' ) OR ( (LCASE(art.Artikelnaam2) like '%a4%' )
AND (LCASE(art.Artikelnaam2) like '%papier%'))  OR  (LCASE(art.Artikelnr_leverancier)
like '%a4 papier%' ) OR ( (LCASE(art.Artikelnr_leverancier) like '%a4%' )
AND (LCASE(art.Artikelnr_leverancier) like '%papier%'))  OR  (LCASE(art.Merk) like '%a4 papier%' ) OR ( (LCASE(art.Merk) like '%a4%' )
AND (LCASE(art.Merk) like '%papier%'))  OR  (LCASE(art.EAN) like '%a4 papier%' ) OR (
(LCASE(art.EAN) like '%a4%' )
AND (LCASE(art.EAN) like '%papier%'))  OR  (LCASE(art.AltArtnr1) like '%a4 papier%' ) OR    
( (LCASE(art.AltArtnr1) like '%a4%' )
AND (LCASE(art.AltArtnr1) like '%papier%'))  OR  (LCASE(art.AltArtnr2) like '%a4 papier%' ) OR ( (LCASE(art.AltArtnr2) like '%a4%' )
AND (LCASE(art.AltArtnr2) like '%papier%')) ))
AND tr.NODELEVEL =5  and tr.LINKTYPE <> 5
ORDER BY tr.NodePosition LIMIT 30)
as some_table group by IdLink;

Answer 2

這可能現在有點舊了，但希望仍然有用。

一般來說，操作的不同和順序需要排序。 排序由索引輔助。 考慮為order by子句指定的列創建索引 - NodePosition，我可以看到的唯一其他索引是與另一列復合，因此訂單不會查詢索引。 對於distinct，您可以嘗試為tr.IdLink，tr.IdTargetLink，tr.IdItem，tr.NodePosition列或單獨創建復合索引。 （我不太確定索引會對多大程度有所幫助，但值得一試）。

其他需要考慮的事項：您的where子句使用函數 - 在此上下文中使用的函數將導致全表掃描，甚至可能無法查看索引。 我不相信mySql支持基於函數的索引，不確定FireBird。 但是可以通過創建另一個可以保存LOWER（列）結果的列來解決它，如果可用的話，您需要使用觸發器來維護該列。

OR條件和LIKE'％a4％'也將導致全表掃描。 我意識到您的業務邏輯可能不允許您從'％a4％'字符串的開頭刪除通配符char，以便可能改進此類用例，您可以考慮子查詢 - 首先嘗試縮小結果集的范圍。可能在子查詢中避免任何LIKE或OR，然后用父查詢包裝該結果，這將進一步過濾結果（將子查詢放入FROM子句）。 因此，在子查詢中，您將具有以下條件：tr.ItemType = 2 AND tr.Market1 = 1且tr.NODELEVEL = 5且tr.LINKTYPE <> 5