本文为【第二讲 Delphi操作数据库基础(下)】的汉字拼音对照版显示拼音
在zai本ben讲jiang中zhong,我wo们men重chong点dian介jie绍shao一yi下xiaBDE和he数shu据ju库ku别bie名ming的de有you关guan知zhi识shi,这zhe是shi操cao作zuo数shu据ju库ku的de基ji础chu。
要yao想xiang学xue习xi写xie数shu据ju库ku程cheng序xu,首shou先xian必bi须xu对duiBDE要yao有you所suo了le解jie。BDE有you一yi个ge操cao作zuo介jie面mian供gong用yong户hu在zai写xie程cheng序xu时shi对dui数shu据ju库ku进jin行xing配pei置zhi一yi些xie信xin息xi,安an装zhuang完wan毕bi后hou在zai程cheng序xu组zu中zhong可ke以yi直zhi接jie找zhao到dao执zhi行xing,其qi执zhi行xing程cheng序xu为weibdeadmin.exe,运yun行xing它ta会hui出chu现xian如ru下xia的de介jie面mian。
介jie面mian的de左zuo半ban部bu分fen有you两liang个ge选xuan项xiang卡ka,一yi个ge是shiDataBase,另ling一yi个ge是shiConfiguaration,我wo们men先xian来lai介jie绍shaoDatabase。
单dan击jiDatabase选xuan项xiang卡ka,将jiang会hui列lie出chu目mu前qian系xi统tong中zhong所suo有you的de数shu据ju库ku别bie名ming。那na么me数shu据ju库ku别bie名ming是shi什shen么me呢ne?数shu据ju库ku别bie名ming是shi初chu学xue用yongDelphi进jin行xing数shu据ju库ku编bian程cheng首shou先xian碰peng到dao的de一yi个ge问wen题ti。Delphi中zhong的de许xu多duo数shu据ju库ku组zu件jian都dou需xu要yao指zhi明ming数shu据ju库ku名ming称cheng,数shu据ju库ku名ming称cheng可ke以yi直zhi接jie指zhi定ding,如ruC:\DATA\DEMO.MDB,但dan在zai代dai码ma中zhong可ke能neng多duo处chu需xu要yao使shi用yong数shu据ju库ku名ming称cheng,如ru果guo都dou这zhe样yang直zhi接jie使shi用yong数shu据ju库ku的de绝jue对dui路lu径jing名ming称cheng,写xie起qi来lai比bi较jiao麻ma烦fan,但dan更geng麻ma烦fan的de事shi情qing在zai于yu如ru果guo用yong户hu改gai变bian了le数shu据ju库ku的de存cun放fang路lu径jing(如ru在zai安an装zhuang时shi让rang用yong户hu指zhi定ding安an装zhuang目mu录lu)或huo数shu据ju库ku名ming称cheng,已yi编bian写xie好hao的de程cheng序xu(EXE文wen件jian)将jiang无wu法fa正zheng常chang工gong作zuo,即ji使shi在zai编bian程cheng阶jie段duan,也ye要yao对dui所suo有you的de代dai码ma都dou进jin行xing修xiu改gai,是shi否fou太tai麻ma烦fan了le,此ci时shi我wo们men最zui好hao给gei数shu据ju库ku另ling取qu一yi个ge名ming字zi,这zhe就jiu是shi别bie名ming,此ci别bie名ming代dai替ti数shu据ju库ku的de真zhen实shi路lu径jing、名ming称cheng,用yong户hu在zai编bian程cheng中zhong不bu必bi考kao虑lv数shu据ju库ku存cun放fang在zai何he处chu,如ru果guo数shu据ju库ku的de绝jue对dui路lu径jing或huo名ming称cheng修xiu改gai了le,只zhi需xu修xiu改gai别bie名ming的de配pei置zhi信xin息xi即ji可ke,用yong户hu的de程cheng序xu无wu需xu做zuo任ren何he修xiu改gai。还huan有you另ling外wai一yi个ge重chong要yao的de原yuan因yin是shi:在zai设she定ding数shu据ju库ku别bie名ming时shi,用yong户hu需xu要yao指zhi明ming数shu据ju库ku类lei型xing,这zhe样yangDelphi才cai知zhi道dao使shi用yong什shen么me样yang的de数shu据ju库ku驱qu动dong程cheng序xu。如ru果guo直zhi接jie用yong数shu据ju库ku绝jue对dui路lu径jing和he数shu据ju库ku真zhen实shi名ming称cheng,在zai使shi用yong时shi需xu要yao在zai程cheng序xu中zhong用yong代dai码ma指zhi定ding数shu据ju库ku类lei型xing,这zhe样yang做zuo实shi在zai太tai麻ma烦fan了le。所suo以yi,建jian议yi还huan是shi使shi用yong数shu据ju库ku别bie名ming。
数shu据ju库ku别bie名ming设she定ding和he数shu据ju库ku连lian接jie。这zhe里li就jiu如ru何he设she定ding数shu据ju库ku别bie名ming做zuo详xiang细xi的de介jie绍shao。这zhe也ye是shi初chu学xue者zhe用yongDelphi进jin行xing数shu据ju库ku编bian程cheng时shi比bi较jiao头tou疼teng的de一yi个ge问wen题ti。许xu多duo有you关guan书shu籍ji都dou讲jiang的de不bu详xiang细xi,即ji使shi讲jiang也ye只zhi是shi用yong标biao准zhun格ge式shi(.DBF .DB )做zuo一yi下xia示shi范fan,对dui目mu前qian流liu行xing的deAccess等deng数shu据ju库ku没mei有you介jie绍shao。这zhe里li将jiang举ju例li说shuo明ming对dui不bu同tong格ge式shi的de数shu据ju库ku如ru何he设she定ding别bie名ming
标biao准zhun格ge式shi的de数shu据ju库ku(STANDARD)
Delphi的de标biao准zhun格ge式shi数shu据ju库ku指zhi的de是shiParadox的de数shu据ju库ku(扩kuo展zhan名ming为weiDB)和hedBase类lei型xing的de数shu据ju库ku(扩kuo展zhan名ming为weiDBF)。对dui这zhe两liang种zhong数shu据ju库ku,在zai设she定ding数shu据ju库ku组zu件jian的deDataBaseName属shu性xing时shi可ke以yi不bu需xu要yao别bie名ming,直zhi接jie输shu入ru.DB、.DBF文wen件jian所suo在zai的de路lu径jing即ji可ke。如ru:C:\Data。但dan基ji于yu上shang面mian所suo述shu原yuan因yin,我wo们men最zui好hao还huan是shi设she定ding数shu据ju库ku别bie名ming。对duiParadox、Foxpro、dBase类lei型xing的de数shu据ju库ku,在zaiBDE Administrator的deObject菜cai单dan中zhong执zhi行xing“new…”菜cai单dan项xiang(或huo在zaiBDE界jie面mian内nei任ren何he处chu单dan击ji鼠shu标biao右you键jian即ji可ke弹tan出chu快kuai捷jie菜cai单dan,从cong中zhong选xuan择ze“new…”),将jiang会hui弹tan出chu一yi个ge数shu据ju库ku驱qu动dong程cheng序xu名ming窗chuang体ti,默mo认ren格ge式shi为weiSTANDARD。单dan击ji“OK”按an钮niu,在zaiDataBase卡ka中zhong出chu现xian新xin的de数shu据ju库ku别bie名ming“STANDARD1”,用yong户hu可ke以yi修xiu改gai为wei自zi己ji所suo喜xi欢huan的de名ming字zi,这zhe里li我wo们men修xiu改gai为wei“mydatabase”,在zai右you边bian的de“Definition”卡ka中zhong用yong户hu可ke定ding义yi数shu据ju驱qu动dong程cheng序xu,单dan击ji“DEFAULT DRIVER”后hou的de输shu入ru框kuang从cong列lie表biao中zhong选xuan择ze,这zhe里li我wo们men选xuan择zeparadox。接jie下xia来lai设she定dingPATH参shen数shu,单dan击jiPATH后hou输shu入ru框kuang,可ke直zhi接jie输shu入ruC:\Data,或huo单dan击ji后hou面mian的de选xuan择ze目mu录lu按an钮niu打da开kai类lei似si于yu文wen件jian夹jia管guan理li器qi的de界jie面mian来lai选xuan择ze数shu据ju表biao文wen件jian目mu录lu。然ran后hou在zai“mydatabase”数shu据ju库ku别bie名ming上shang单dan击ji右you键jian,选xuan择ze“Apply”(应ying用yong)即ji可ke。这zhe样yangmydatabase就jiu是shi数shu据ju库kuC:\Data(此ci路lu径jing下xia为wei数shu据ju表biao)的de别bie名ming。
Access数shu据ju库ku别bie名ming的de设she定ding和he连lian接jie
Delphi自zi3.0版ban本ben开kai始shi对duiAccess数shu据ju库ku提ti供gong了le支zhi持chi。对duiAccess数shu据ju库ku的de支zhi持chi有you两liang种zhong连lian接jie方fang式shi。一yi种zhong是shi本ben地di(Native)数shu据ju库ku连lian接jie,另ling一yi种zhong是shiODBC(Open Database Connectivity)开kai放fang式shi数shu据ju库ku连lian接jie。本ben地di方fang式shi(native),同tong前qian面mianDBF格ge式shi数shu据ju库ku别bie名ming设she定ding步bu骤zhou类lei似si,在zai创chuang建jian新xin的de别bie名ming(这zhe里li别bie名ming为weitest.mdb)时shi,从congDatabase Driver Name下xia拉la列lie表biao中zhong选xuan择ze“MSACCESS”,在zaiDefinition卡ka中zhong设she定ding好haoDataBase Name如ru“C:\Data\Demo.mdb”,LANGDRIVER参shen数shu中zhong可ke选xuan择ze“Access General”,因yin为wei似si乎huBDE没mei有you提ti供gong象xiangDBF数shu据ju库ku那na样yang中zhong文wen语yu言yan驱qu动dong,其qi余yu的de参shen数shu可ke不bu输shu入ru。
ODBC方fang式shi。用yong这zhe种zhong方fang式shi主zhu要yao是shi对dui数shu据ju源yuan进jin行xing设she定ding(其qi实shi就jiu是shi设she定ding数shu据ju库ku别bie名ming)。初chu学xue者zhe对duiODBC一yi般ban感gan到dao很hen深shen奥ao,其qi实shi并bing不bu神shen秘mi,下xia面mian详xiang细xi说shuo明ming操cao作zuo方fang法fa。在zaiwin9X控kong制zhi面mian板ban中zhong的de“32位weiODBC”,双shuang击ji打da开kaiODBC 数shu据ju源yuan管guan理li器qi,如ru图tu2-2所suo示shi。
单dan击ji“添tian加jia”按an钮niu后hou界jie面mian如ru图tu2-3,从cong中zhong选xuan择ze驱qu动dong程cheng序xu,这zhe里li选xuan择ze“Microsoft Access Driver(*.mdb)”,单dan击ji“完wan成cheng”,界jie面mian为wei图tu2-4所suo示shi。在zai“数shu据ju源yuan名ming(N):”输shu入ru数shu据ju源yuan名ming称cheng如ru“myAccess ”,单dan击ji“数shu据ju库ku”框kuang中zhong的deDataBase的de“选xuan取qu(S)…”按an钮niu选xuan择ze要yao打da开kai的deMDB数shu据ju库ku,再zai单dan击ji“高gao级ji”按an钮niu,在zai这zhe里li可ke输shu入ru“设she定ding名ming称cheng”、“密mi码ma”,无wu密mi码ma不bu输shu。
单dan击ji“确que定ding”返fan回hui后hou再zai单dan击ji“确que定ding”按an钮niu,返fan回hui界jie面mian(图tu2-5),从cong中zhong可ke发fa现xian用yong户hu刚gang设she定ding的de数shu据ju源yuan名ming称cheng“myAccess file”已yi经jing出chu现xian在zai列lie表biao中zhong,如ru要yao修xiu改gai可ke单dan击ji“配pei置zhi”按an钮niu,无wu误wu后hou单dan击ji“确que定ding”退tui出chu。至zhi此ci,我wo们men已yi正zheng确que设she定ding了le数shu据ju源yuan。下xia面mian打da开kaiBDEAdministrator,
你ni会hui发fa现xian什shen么me?别bie名ming列lie表biao中zhong出chu现xian了le“myAccess ”,它ta就jiu代dai表biao了leC:\Data\demo.mdb数shu据ju库ku。也ye就jiu是shi说shuo在zaiODBC中zhong设she定ding的de数shu据ju源yuan名ming称cheng就jiu是shi数shu据ju库kudemo.mdb的de别bie名ming,不bu需xu要yaoBDE设she定ding就jiu可ke以yi使shi用yong了le(如ru需xu要yao可ke以yi在zaiBDE中zhong设she定ding一yi下xia其qi它ta的de参shen数shu),在zai数shu据ju库ku组zu件jian的deDataBaseName属shu性xing列lie表biao中zhong选xuan中zhong它ta就jiu可ke以yi使shi用yong了le。
如ru果guo不bu满man意yi这zhe个ge别bie名ming(数shu据ju源yuan名ming)可ke以yi按an下xia面mian的de方fang法fa去qu做zuo,在zaiBDE中zhong创chuang建jian新xin的de别bie名ming时shi在zaiDadabase Driver Name 中zhong选xuan择ze“Microsoft Access Driver(*.mdb)”,然ran后hou输shu入ru新xin的de别bie名ming。如ru“myAccess good”,在zaiDefinition卡ka中zhong设she定ding参shen数shuODBC DSN时shi选xuan择ze“myAccess” (数shu据ju源yuan名ming) 。其qi它ta的de就jiu和he前qian面mian一yi样yang了le。这zhe样yangmyAccess good就jiu是shidemo.mdb数shu据ju库ku的de别bie名ming。如ru果guo这zhe样yang做zuodemo.mdb就jiu有you了le两liang个ge别bie名ming了le,建jian议yi直zhi接jie用yong数shu据ju源yuan名ming做zuo别bie名ming(这zhe样yang简jian单dan些xie)。
另ling外wai一yi种zhong在zaiBDE中zhong直zhi接jie建jian立liODBC方fang式shi的de方fang法fa是shi:单dan击ji鼠shu标biao右you键jian,选xuan择ze”new”,从congDatabase Driver Name下xia拉la列lie表biao中zhong选xuan择ze“Microsoft Access Driver(*.mdb)”,自zi动dong生sheng成cheng一yi个ge如ruODBC1的de数shu据ju库ku别bie名ming,你ni可ke以yi把ba它ta修xiu改gai为wei自zi己ji喜xi爱ai的de名ming字zi。在zai别bie名mingODBC1上shang单dan击ji鼠shu标biao邮you件jian,选xuan择ze“ODBC Administrator”也ye可ke以yi打da开kaiODBC数shu据ju源yuan管guan理li器qi。其qi余yu的de步bu骤zhou同tong上shang。但dan这zhe里li常chang会hui出chu现xian一yi些xie问wen题ti,在zai为weiODBC1设she定ding参shen数shuODBC DSN时shi会hui找zhao不bu到dao刚gang设she定ding的de数shu据ju源yuan,新xin设she定ding的de数shu据ju源yuan也ye不bu会hui以yi别bie名ming的de方fang式shi出chu现xian,需xu要yao关guan闭biBDE再zai重chong新xin打da开kai才cai行xing。不bu如ru直zhi接jie在zai控kong制zhi面mian板ban中zhong打da开kaiODBC设she定ding数shu据ju源yuan来lai的de方fang便bian。其qi实shi,对dui于yuODBC方fang式shi访fang问wen数shu据ju库ku,可ke以yi说shuoBDE只zhi起qi到dao一yi个ge简jian单dan的de管guan理li作zuo用yong,并bing没mei有you太tai多duo的de实shi际ji意yi义yi。
Excel文wen件jian的de工gong作zuo表biao别bie名ming设she定ding
对dui于yuExcel文wen件jian来lai说shuo,也ye需xu要yao使shi用yongODBC建jian立li数shu据ju源yuan,方fang法fa和he用yongODBC建jian立liAccess
数shu据ju库ku别bie名ming是shi一yi样yang的de,可ke参shen考kao上shang面mian的de介jie绍shao。
服fu务wu器qi数shu据ju库ku别bie名ming设she定ding。服fu务wu器qi数shu据ju库ku如ruOracle、Sybase、Informix、Microsoft SQL Server、 Intrbase等deng,它ta们men的de别bie名ming设she定ding可ke以yi用yong本ben地di或huoODBC方fang式shi设she定ding(需xu要yao安an装zhuang驱qu动dong程cheng序xu)。和he前qian面mian设she定ding别bie名ming的de操cao作zuo基ji本ben一yi样yang。不bu一yi样yang的de地di方fang主zhu要yao为wei在zaiDefinition参shen数shu设she定ding中zhong有you一yi个ge数shu据ju库ku服fu务wu器qi名ming称cheng(Server Name)需xu要yao正zheng确que设she定ding。
这zhe里li说shuo明ming一yi点dian:对dui于yu本ben地di数shu据ju库ku如rudBase、Foxpro、Paradox数shu据ju库ku也ye可ke用yongODBC方fang式shi访fang问wen,只zhi不bu过guo一yi般ban没mei有you必bi要yao。
用yongSQL Explore建jian立li数shu据ju库ku别bie名ming和he连lian接jie
在zaiDelphi5.0的deDataBase菜cai单dan中zhong有you一yi个geExplore菜cai单dan项xiang,执zhi行xing它ta将jiang出chu现xianSQL Explorer运yun行xing窗chuang口kou,和heBDE的de运yun行xing界jie面mian非fei常chang相xiang似si,在zai这zhe里li进jin行xing建jian立li别bie名ming和he连lian接jie的de操cao作zuo和he在zaiBDE中zhong完wan全quan一yi样yang。用yongSQLExplore建jian立li别bie名ming和he连lian接jie的de优you点dian是shi,建jian立li好hao别bie名ming和he连lian接jie后hou,在zai右you边bian的de窗chuang体ti中zhong可ke打da开kai数shu据ju表biao、查cha看kan字zi段duan属shu性xing、查cha看kan数shu据ju表biao内nei容rong、进jin行xingSQL操cao作zuo。
下xia面mian我wo们men来lai介jie绍shao一yi下xiaConfiguaration选xuan项xiang卡ka。此ci选xuan项xiang主zhu要yao用yong来lai供gong用yong户hu查cha看kan、修xiu改gai驱qu动dong程cheng序xu及ji系xi统tong的de配pei置zhi信xin息xi。分fen两liang大da部bu分fen,一yi是shiDriver。Driver下xia又you分fen为weinative(本ben地di方fang式shi)和heODBC方fang式shi,本ben地di方fang式shi下xia列lie出chu了le目mu前qian可ke用yong的de本ben地di数shu据ju库ku及ji驱qu动dong配pei置zhi,我wo们men选xuan择zeMSACCESS来lai看kan看kan右you边bian列lie出chu的de信xin息xi,其qi中zhong重chong要yao的de两liang个ge配pei置zhi为wei:DLL32:IDDA3532.DLL ,DATABASENAME 为wei:DRIVE:/PATH/DATABASE.MDB,前qian者zhe说shuo明ming数shu据ju库ku驱qu动dong程cheng序xu,后hou者zhe说shuo明ming数shu据ju库ku名ming称cheng的de输shu入ru方fang式shi应ying该gai是shi驱qu动dong器qi/路lu径jing/MDB数shu据ju库ku名ming字zi。这zhe里li顺shun便bian说shuo一yi下xia,用yongdelphi5或huodelphi4自zi带dai的de制zhi做zuo安an装zhuang盘pan的de软ruan件jianIS Express制zhi做zuo出chu来lai的deMSAccess数shu据ju库ku的de安an装zhuang程cheng序xu把baBDE打da包bao安an装zhuang后hou,运yun行xing执zhi行xing文wen件jian,总zong会hui出chu现xian非fei法fa错cuo误wu,经jing仔zai细xi检jian查cha发fa现xian安an装zhuang后houDLL32设she定ding的de是shiIDDAO32.DLL,将jiang其qi修xiu改gai为weiIDDA3532.DLL就jiu可ke以yi正zheng常chang运yun行xing了le。ODBC下xia列lie出chu的de是shi目mu前qian可ke用yong的deODBC驱qu动dong程cheng序xu的de配pei置zhi信xin息xi。二er是shisystem,在zaisystem下xia设she定ding的de是shi通tong用yong的de系xi统tong配pei置zhi信xin息xi。其qi中zhongINIT设she定ding的de是shi设she计ji一yi个ge应ying用yong系xi统tong的de初chu始shi默mo认ren设she置zhi。FORMAT下xia可ke设she定dingDATE、TIME、NUMBER三san个ge常chang用yong配pei置zhi信xin息xi。
在zaiDATE中zhong,我wo们men可ke以yi设she定ding如ru下xia:
SEPARATOR 用yong来lai确que定ding用yong什shen么me样yang的de分fen隔ge符fu来lai将jiang年nian、月yue、日ri分fen开kai。
MODE 控kong制zhi如ru何he显xian示shi日ri期qi格ge式shi,有you三san种zhong方fang式shi:0-MDY,1- DMY, 2-YMD,按an中zhong国guo人ren的de习xi惯guan应ying该gai为wei2(年nian月yue日ri),在zai安an装zhuangBDE时shi缺que省sheng将jiang根gen据ju控kong制zhi面mian板ban中zhong的de设she定ding配pei置zhi。
FOURDIGITYEAR是shi否fou采cai用yong四si位wei年nian份fen,缺que省sheng情qing况kuang是shi用yong2位wei,只zhi不bu过guo现xian在zai我wo们men都dou应ying该gai用yong四si位wei了le。如ru果guo设she定ding为weifalse, 则ze在zai01/01/00 至zhi12/31/49将jiang被bei认ren为wei是shi21世shi纪ji,如ru果guo在zai01/01/50 至zhi12/31/99被bei认ren为wei属shu于yu20世shi纪ji
YEARBIASED设she定ding是shi否fou将jiang用yong户hu输shu入ru的de两liang位wei年nian份fen在zai保bao存cun时shi改gai为wei4位wei,缺que省sheng为weiTRUE.
LEADINGZEROM 设she定ding是shi否fou将jiang用yong户hu输shu入ru的de10月yue份fen以yi前qian的de月yue份fen自zi动dong添tian加jia0,比bi如ru将jiang1/1/80 变bian为wei01/1/80
LEADINGZEROD 设she定ding是shi否fou将jiang用yong户hu输shu入ru的de10日ri以yi前qian的de日ri期qi自zi动dong添tian加jia0,比bi如ru将jiang1/1/80 变bian为wei1/01/80
至zhi于yuTIME和heNUMBER设she定ding就jiu很hen简jian单dan了le,读du者zhe自zi己ji看kan看kan就jiu明ming白bai了le。
通tong过guo这zhe一yi讲jiang我wo们men知zhi道dao如ru何he设she定ding常chang用yong类lei型xing的de数shu据ju别bie名ming了le,下xia一yi讲jiang我wo们men就jiu开kai始shi设she计ji一yi个ge数shu据ju库ku应ying用yong程cheng序xu并bing讲jiang解jie用yong到dao的de数shu据ju库ku组zu件jian等deng内nei容rong了le,希xi望wang读du者zhe能neng坚jian持chi读du下xia去qu!
【原文】