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Chng 1T NG QUAN V MICROSOFT ACCESS 20101.1. Gi i thi u:Microsoft Access l m t thnh ph n trong b Microsoft Office c a hng Microsoft. MS Access cung c p cho ng i dng giao di n thn thi n v cc thao tc n gi n, tr c quan trong vi c xy d ng v qu n tr c s d li u cng nh xy d ng cc ng d ng c s d li u. Access l m t h qu n tr c s d li u quan h (RDMS- Relational Database Management System), r t ph h p cho cc bi ton qu n l v a v nh . Hi u nng cao v c bi t d s d ng do giao di n gi ng cc ph n m m khc trong b MS Office nh MS Word, MS Excel. Access cn cung c p h th ng cng c pht tri n kh m nh i km (Development Tools) gip cc nh pht tri n ph n m m n gi n trong vi c xy d ng tr n gi cc d n ph n m m qu n l qui m v a v nh MS Access 2010 cung c p h th ng cng c r t m nh, gip ng i dng nhanh chng v d dng xy d ng chng trnh ng d ng thng qua query, form, report k t h p v i m t s l nh Visual Basic. Trong Microsoft Access 2010, b n c th xy d ng c s d li u web v a chng ln cc SharePoint site. Ng i duy t SharePoint c th s d ng ng d ng c s d li u c a b n trong m t trnh duy t web, s d ng SharePoint xc nh ai c th xem nh ng g. Nhi u c i ti n m i h tr kh nng a d li u ln web, v cng cung c p l i ch trong vi c xy d ng c s d li u trn my n truy n th ng. Access 2010 giao di n ng i dng cng thay i. N u b n khng quen v i Office Access 2007, Ribbon v C a s Danh m c chnh c th l m i cho b n. Thanh Ribbon ny thay th cc menu v thanh cng c t phin b n tr c. C a s Danh m c chnh thay th v m r ng cc ch c nng c a c a s Database.-1-

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V m t i m m i trong Access 2010, Backstage View cho php b n truy c p vo t t c cc l nh p d ng cho ton b c s d li u, nh l thu g n v s a ch a, ho c cc l nh t menu File. Cc l nh c b tr trn cc tab pha bn tri c a mn hnh, v m i tab ch a m t nhm cc l nh c lin quan ho c cc lin k t. V d , n u b n nh n New, b n s th y t p h p cc nt cho php b n t o ra m t c s d li u m i t u, ho c b ng cch ch n t m t th vi n c a c s d li u cc m u thi t k chuyn nghi p.

1.2. Kh i ng Access 2010: kh i ng MS Access ta c th dng m t trong cc cch sau: (All) Cch 1: Start Programs Microsoft Office Microsoft Office Access 2010. Cch 2: Double click vo shortcut Ms Access trn desktop, xu t hi n c a s kh i ng Access nh hnh.

1.3. Cc thnh ph n trong c a s kh i ng: 1.3.1. Thanh Quick Access:Thanh cng c Quick Access: Hi n th bn tri c a thanh tiu , m c nh thanh Quick Access g m cc nt cng c Save, Undo, Bn ph i c a Quick Access ch a nt Customize, khi c s d li u ang m , n u click nt Customize s xu t hi n m t menu gip b n ch nh cc nt l nh hi n th trn thanh Quick Access, n u cc l nh khng c trong menu, b n c th click nt More-2-

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Commands ho c click ph i trn thanh Quick Access ch n Customize Quick Access Toolbar. thm nt l nh vo Quick Access, b n ch n l nh trong khung choose commands from, click nt Add click OK.

1.3.2. Vng lm vi c:Khi kh i ng Access, trong c a s kh i ng, m c nh tab File v l nh New trong tab File c ch n, c a s c chia thnh 3 khung: Khung bn tri g m cc l nh trong tab File Khung gi a: ch a cc lo i t p tin c s d li u m b n c th t o m i. Khung bn ph i: nh p tn v ch n v tr lu t p tin m i t o v th c thi l nh t o m i c s d li u.

1.3.3. Thanh Ribbon:Bn d i thanh tiu , Access 2010 hi n th cc nt l nh trn m t thanh di c g i l Ribbon, thanh Ribbon c th chi m nhi u khng gian mn hnh, ta c th thu nh kch th c c a Ribbon b ng cch click nt Minimize The Ribbon

Thanh Ribbon c t o b i nhi u tab khc nhau, truy c p vo m t tab b n c th click-3-

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trn nhn c a tab ho c dng phm t t. Nh n phm Alt ho c F10 hi n th tn c a cc phm t t c a cc tab. H u h t cc tab trn Ribbon c chia thnh t ng nhm khc nhau, m i nhm hi n th tiu con bn d i c a nhm. M t s nhm trong Ribbon c hi n th nt , khi click nt ny s xu t hi n c a s cho php thi t l p cc thu c tnh c a nhm tng ng.

1.3.4. C a s PropertiesC a s Properties gip b n c th hi u ch nh thu c tnh c a i t ng, ty theo i t ng ang c ch n m c a s thu c tnh s ch a nh ng thu c tnh tng ng c a i t ng . m c a s Properties, b n ch n i t ng mu n thay i thu c tnh, ch n tab Design ho c nh n t h p phm Atl +Enter C a s Properties c chia thnh nm nhm Format: G m cc thu c tnh nh d ng i t ng Data: G m cc thu c tnh truy su t d Event: G m cc s ki n (event) c a Other: G m cc thu c tnh gip b toolbars, All: G m t t c cc thu c tnh trong b

li u c a i t ng. i t ng. n t o h th ng menu, n nhm trn.

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1.3.5. Thanh Navigation PaneNavigation Pane l khung ch a n i dung chnh c a c s d li u. T khung Navigation Pane, b n c th m b t k Table, Query, Form, Report, Macro, ho c module trong c s d li u b ng cch double click vo tn c a i t ng. B ng cch click ph i vo tn c a i t ng trong Navigation Pane, b n c th th c hi n cc thao tc v i i t ng nh: i tn, sao chp, xo, import, export m t i t ng Nh n phm F11 ho c click vo mi tn kp gc trn bn ph i c a khung Navigation Pane hi n th ho c n khung Navigation Pane.

1.4. Cch t o t p tin c s d li u: 1.4.1. T o m t c s d li u m i r ng: T i c a s kh i ng, click nt Blank Database. File name: nh p tn t p tin c s d li u, trong Access 2010,

t p tin c s d li u c lu v i tn c ph n m r ng l .accdb. N u khng ch nh ng d n th m c nh t p tin m i t o s c lu trong th m c Document, ng c l i, click nt Brows ch nh v tr lu t p tin. Click nt Create t o t p tin c s d li u.-5-

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1.4.2. T o c s d li u theo m u (Template) T i c a s kh i ng. Ch n Sample Template ch n m t m u c s d li u c s n. Trong khung File name, nh p tn t p tin c s d li u v click nt Browse ch nh v tr lu t p tin, Click nt create t o c s d li u.

1.5. Qu n l c s d li uSau khi t o c s d li u, ho c m m t c s d li u th Tab File s hi n th cc l nh qu n l t p tin c s d li u.

1.5.1. Recent:M c Recent hi n th danh sch cc t p tin c s d li u c m g n nh t. S t p tin hi n th trong danh sch ny m c nh l 9, c th thay i b ng cch: T i c a s lm vi c c a Access, ch n tab File. Ch n Options Client Settings Trong m c Display, thay i gi tr c a thu c tnh Show This Number Of Recent Documents Click OK.

1.5.2. M m t c s d li u: m m t c s d li u c ta th c hi n m t trong cc cch sau:-6-

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Cch 1: T i c a s kh i ng, trong tab File Open Ch n t p tin c s d li u c n m Open. Cch 2: Double click vo tn t p tin c n m .

1.5.3. Thot kh i access:C th thot kh i Access b ng m t trong cc cch: Ch n menu File Exit Nh n t h p phm Alt + F4; Ho c s d ng nt Close trn c a s Access ang m .

1.5.4. Thu g n v ch nh s a c s d li u (Compact & Repair Database)Khi t o thm i t ng trong c s d li u th dung l ng c a t p tin c s d li u s tng ln, khi xa m t i t ng th vng nh c a n s r ng, nhng khng s d ng c. Ch c nng Compact & Repair Database gip thu h i l i ph n b nh b r ng, lm cho t p tin c s d li u g n l i. Cch th c hi n: M c s d li u c n thu g n v ch nh s a Click nt Compact & Repair Database

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1.5.5. T o password M c s d li u ch Exclusive b ng cch: File Open Open Exclusive. Ch n tab File Ch n l nh Info Click nt set Database Password Nh p Password 2 l n OK

1.5.6. G b password M c s d li u ch Exclusive: File Open Open Exclusive Trong tab File, ch n l nh Info Click nt UnSet Database Password.

1.6. Cc i t ng trong c s d li u trong AccessC s d li u l m t t p h p nh ng s li u lin quan n m t m c ch qu n l, khai thc d li u no , CSDL trong Access l c s d li u quan h g m cc thnh ph n: Tables, Querys, Forms, Reports, Pages, Macros, Modules.

1.6.1. B ng (Tables):Table l thnh ph n quan tr ng nh t c a t p tin c s d li u Access, dng lu tr d li u. Do y l i t ng ph i c-8-

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t o ra tr c. Bn trong m t b ng, d li u c lu thnh nhi u c t v nhi u dng.

1.6.2. Truy v n (Queries):Query l cng c ng i s d ng truy v n thng tin v th c hi n cc thao tc trn d li u. Ng i s d ng c th s d ng ngn ng SQL ho c cng c QBE thao tc trn d li u.

1.6.3. Bi u m u (Forms):Form l cng c thi t k giao di n cho chng trnh, dng c p nh t ho c xem d li u. Bi u m u gip thn thi n ha qu trnh nh p, thm, s a, xa v hi n th d li u.

1.6.4. Bo co (Reports):Report l cng c gip ng i dng t o cc k t xu t d li u t cc b ng, sau nh d ng v s p x p theo m t khun d ng cho tr c v c th in ra mn hnh ho c my in.

1.6.5. T p l nh (Macros):Macro l m t t p h p cc l nh nh m th c hi n m t lo t cc thao tc c qui nh tr c. T p l nh c a Access c th c xem l m t cng c l p trnh n gi n p ng cc tnh hu ng c th .

1.6.6. B m l nh (Modules):L cng c l p trnh trong mi tr ng Access m ngn ng n n t ng c a n l ngn ng Visual Basic for Application. y l m t d ng t ng ha chuyn su hn t p l nh, gip t o ra nh ng hm ng i dng t nh ngha. B m l nh th ng dnh cho cc l p trnh vin chuyn nghi p. Cng c t o cc i t ng trong Access c t ch c thnh t ng nhm trong tab Create c a thanh Ribbon

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1.7. Thao tc v i cc i t ng trong c s d li u: lm vi c trn i t ng, ta ch n i t ng trn thanh Access object, cc thnh vin c a i t ng s xu t hi n bn d i tn c a i t ng.

1.7.1. T o m i m t i t ng: Click tab Create trn thanh Ribbon. Trong nhm cng c c a t ng i t ng, ch n cch t o tng ng.

1.7.2. Thi t k l i m t i t ng: N u i t ng ang ng: Click ph i trn i t ng c n thi t k l i. Ch n Design view. N u i t ng ang m : Click nt Design View.

1.7.3. Xem n i dung trnh by c a m t i t ng: N u i t ng ang m ch Design View Click nt View. N u i t ng ang ng: Click ph i trn tn i t ng c n xem. Ch n Open.

1.7.4. Xa m t i t ng. Click ph i chu t trn i t ng c n xa, Ch n m c delete trn Menu Popup. Ho c ch n r i nh n phm Delete. Ho c nt c .

trn thanh cng

1.7.5. i tn i t ng Click ph i chu t trn i t ng, ch n rename, Ho c nh n F2 Nh p tn m i.-10-

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1.7.6. Sao chp m t i t ng Click ph i chu t ln thnh vin c n chp Ch n m c copy chp i t ng vo Clipboard. Click nt Paste trn thanh Menu chp vo c a s database. Nh p tn cho i t ng sao chp. i v i ki u i t ng Table, ta c th l a ch n 1 trong 3 ki u sao chp Structure only: Sao chp c u trc Structure and data: Sao chp c u trc v d li u Append Data to Exiting Table: Thm d li u vo m t b ng ang t n t i.

1.7.7. Chp d li u t Access sang ng d ng khc (Export).C th xu t d li u sang c s Excel,Word, Pdf d li u Access khc, ho c

Cch th c hi n: Ch n i t ng mu n xu t sang ng d ng khc. Ch n tab External Data. Trong nhm cng c Export, ch n lo i ng d ng m b n mu n xu t d li u: Excel, Text file, XML file, Word, Access

Click nt Browse ch nh v tr xu t d li u. Click OK hon t t vi c export d li u.

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1.7.8. Chp d li u t ng d ng khc vo c s d li u Access hi n hnh (Import)C th chp d li u t ng d ng khc nh Excel, ODBC Database, XML file, Access, vo c s d li u hi n hnh. Cch th c hi n:

Ch n tab External Data. Trong nhm l nh Import & Link, ch n ng d ng m b n mu n chp d li u. L n l t lm theo cc b c h ng d n c a Access.

a. Chp d li u t Excel vo Access Trong c a s lm vi c c a Access, ch n tab External Data, click nt Excel trong nhm l nh Import & Link. Ch n t p tin Excel c n chp (Click nt Browse tm t p tin Excel) Open OK, sau th c hi n theo cc b c h ng d n c a Access + Ch n sheet ch a d li u c n chp, Next. + Ch n dng lm tiu cho b ng, Next.

+ Ch nh thu c tnh cho cc field + Ch n cch t o kha cho b ng-12-

Next.

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Let Access add primary key: Access t t o kha. Chose my own primary key: B n ch nh kha. No primary key: Khng t o kha. + Nh p tn cho b ng Finish. + Access hi n th thng bo cho bi t hon t t qu trnh import m t file Excel thnh m t b ng trong Access.

b. Chp d li u t c s d li u Access khc vo c s d li u hi n hnh. Trong c a s lm vi c c a Access, ch n tab External Data, click nt Access trong nhm l nh Import & Link. Ch n t p tin Access ch a d li u c n chp (Click nt Browse tm t p tin Access) Open. Ch n ty ch n Import table, query, form, report, macro and modules into the current database ch nh v tr lu tr d li u trong c s d li u hi n hnh OK Trong c a s Import-13-

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object, ch n i t ng c n chp. C th ch n nhi u ng th i i t ng ho c ch n t t c b ng cch click nt Select All OK.

1.7.9. Ch c nng LinkCh c nng Link trong Acces duy tr m i lin k t v i d li u ngu n. N u d li u ngu n thay i th d li u trong b ng lin k t s thay i theo v ng c l i. Cch th c hi n tng t nh ch c nng Import, nhng trong c a s Get External Data, ta ch n ty ch n Link to data source by creating a link table

Ch n b ng mu n link

OK

1.8. Ch n giao di n ng i dng trong Access 2010Cc phin b n tr c y c a Access cung c p ch m t lo i giao di n ng i dng duy nh t l cc c a s c th ch ng ln nhau. B t u v i Access 2007, v by gi trong Access 2010, b n c s l a ch n c a vi c s d ng cc giao di n truy n th ng ho c lo i giao di n m i c d ng cc tab.

1.8.1. Tabbed DocumentsTabbed Documents l giao di n l t ng cho ng i dng lm vi c v i nhi u hn m t i t ng t i m t th i i m. Trong giao di n ny form v report khng th n m trn u trang c a m t khc v ng i dng c th xem t t c cc i u khi n trn m t i t ng giao di n ng i dng m khng c n ph i di chuy n m t i t ng trong ng i.

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1.8.2. Overlapping WindowsOverlapping Windows c l i th hn. Do s a d ng c a vi c thi t l p thu c tnh BorderStyle v kh nng lo i b cc nt Min, Max, v Close. V i giao di n Overlapping Windows, b n c th d dng bu c ng i dng tng tc v i m t form t i m t th i i m.

1.8.3. Chuy n t giao di n Tabbed Documents sang Overlapping Windows i v i Access 2007 v Access 2010 th khi kh i ng m c nh l giao di n Tabbed Documents chuy n sang d ng Overlapping Windows ta th c hi n nh sau: Trong c a s lm vi c c a Access, ch n tab File ch n l nh Options. Trong c a s Access options, ch n Current Database. Trong m c Document Window Options Ch n Overlapping Windows OK Thot kh i Access v kh i ng l i.-15-

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Chng 2XY D NG C S D LI UXy d ng c s d li u l cng vi c quan tr ng u tin trong ton b qui trnh pht tri n m t ng d ng trn Access. M t c s d li u c thi t k v xy d ng t t s l nh ng thu n l i trong qu trnh pht tri n ng d ng.

2.1. Khi ni m v c s d li u AccessM t c s d li u Access bao g m t p h p cc b ng d li u c quan h ch t ch , ph h p ph c v lu tr d li u cho m t ng d ng qu n l. V d : M t c s d li u Qu n l sinh vin bao g m t p h p cc b ng d li u: SINHVIEN, LOP, MONHOC, KETQUA c k t n i nhau m t cch ph h p ph c v vi c lu tr d li u cho ng d ng qu n l sinh vin. C u trc c s d li u qu n l sinh vin trong Access c m t nh sau:

2.2. B ng d li u (Table) 2.2.1. Khi ni m:B ng (Table): L thnh ph n c b n trong c s d li u c a MS Access. y l i t ng quan tr ng nh t, dng lu tr d li u, m i b ng lu tr thng tin v m t i t ng ang qu n l. M t b ng g m c nhi u c t (field) v nhi u hng (record) C t (Field) : M i field (field ho c c t) trong m t b ng ch ch a m t lo i d li u duy nh t, n lu tr m t thu c tnh c a i t ng.Trong m t b ng ph i c t nh t m t field.-16-

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V d : B ng SINHVIEN, lu tr thng tin c a i t ng sinh vin, g m cc field MASV, HOSV, TENSV, PHAI, NGAYSINH, DIACHI, MALOP.Cc field bi u di n thng tin c a sinh vin Record

Dng (Record): L m t th hi n d li u c a cc field trong b ng. Trong m t b ng c th c khng c record no ho c c nhi u records. Trong m t b ng th d li u trong cc record khng c trng l p.

2.2.2. Kha chnh (Primary key)Kha chnh c a m t b ng l m t ho c nhi u field k t h p m theo Access s xc nh m t record duy nh t trong b ng. D li u trong field kha chnh khng c trng v khng r ng. Thng th ng, trong m i b ng nn c kha chnh t o quan h gi a cc b ng trong c s d li u v MS Access t ng ki m tra rng bu c d li u khi ng i dng nh p li u. V d : trong b ng sinh vin M sinh vin xc nh m t sinh vin duy nh t.Kha chnh

Khi m t field ho c nhi u field k t h p c ch nh l kha chnh th Access s t ng t o ch m c cho chng.

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Khi nh p d li u, Access s t ng ki m tra kha chnh v khng cho php trng l p, v khng r ng.

2.2.3. Kha ngo i (Foreign key)Kha ngo i l m t field hay m t nhm cc field trong m t record c a m t b ng, tr n kha chnh c a m t record khc c a m t b ng khc. Thng th ng, kha ngo i trong m t b ng tr n kha chnh c a m t b ng khc. D li u trong field kha ngo i ph i t n t i trong field kha chnh m n tr t i. Kha ngo i dng t o quan h gi a cc b ng trong c s d li u V d :Kha ngo i Kha chnh

2.3. Cch t o b ng 2.3.1. T o b ng b ng ch c nng Table Design:B c 1: Trong c a s lm vi c c a Access, trn thanh Ribbon, click tab Create, trong nhm l nh Table, click nt l nh Table Design, xu t hi n c a s thi t k b ng g m cc thnh ph n: Field Name: nh ngha cc fields trong b ng. Data Type: ch n ki u d li u lu tr d li u c a field tng ng. Description: dng ch thch ngha c a field. Field Properties: thi t l p cc thu c tnh c a Field, g m c hai nhm: General: l ph n nh d ng d li u cho field trong c t Field Name.-18-

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Lookup: l ph n quy nh d ng hi n th / nh p d li u cho Field .

B c 2: Trong c a s thi t k , th c hi n cc cng vi c sau: Nh p tn field trong c t field Name, ch p nh n kho ng tr ng, khng phn bi t ch hoa, ch th ng. Nn nh p tn field theo tiu ch: Ng n g n, d nh , g i ngha, v khng c kho ng tr ng. Ch n ki u d li u cho field trong c t Data Type Ch thch cho field trong c t Description. Ch nh thu c tnh cho field trong khung Field Properties. B c 3: Xc nh kha chnh cho b ng: t tr t i field c ch n lm kha chnh (ho c ch n cc field ng th i lm kha) Click nt Primary key trn thanh cng c Table (Table Tools), ho c click ph i trn tn field, ch n l nh Primary key. B c 4: Lu b ng v a t o b ng cch: Click vo nt trn thanh Quick Access-19-

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Nh p tn cho b ng trong h p tho i Save as nh hnh (trong tr ng h p Table m i t o, cha t tn). Lu : N u b ng cha c t kha chnh th Access s hi n th m t h p tho i thng bo:

Nh n nt Cancel tr l i c a s thi t k , t kho chnh cho b ng. Nh n nt No lu m khng c n t kha chnh, c th t sau. Nh n nt Yes Access t t o kho chnh c tn l ID, ki u Autonumber.

2.3.2. T o b ng trong ch Datasheet ViewC th t o b ng b ng cch nh ngha tr c ti p cc c t trong ch DataSheet View nh sau: Trong c a s lm vi c c a Access, ch n tab Create trn thanh Ribbon, trong nhm l nh Table, click nt Table, xu t hi n b ng m i ch Datasheet View. Thanh Ribbon chuy n sang tab Field v i nhm l nh Add & Delete gip b n ch n ki u d li u cho Field m i khi thm Field vo b ng.-20-

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t tr trong bn d i Field m i (Click to Add), sau ch n m t trong cc ki u d li u trong nhm Add & Delete trn thanh Ribbon. Ho c click chu t trn Click to Add, ch n ki u d li u trong menu. C th click nt More Fields ch n cc ki u d li u khc. Nh p tn cho Field m i. T o Field tnh ton: Khi thi t k t b ng ch DataSheet View, b n c th t o m t Field m i m n l k t qu c a m t bi u th c tnh ton t cc Field tr c, b ng cch: Click tiu Click to Add c a Field m i nh hnh trn. Ch n l nh Calculated Field, xu t hi n c a s Expression Builder Nh p bi u th c tnh ton.

2.4. Cc ki u d li u (Data Type)Trong access m i Field c th nh n m t trong cc ki u d li u sau:-21-

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Data TypeKi u d li u D li u Kch th c

Vn b n T i a 255 k t Vn b n nhi u dng, nhi u T i a 65.535 k Memo trang t Ki u s (bao g m s nguyn v s th c). dng th c hi n tnh 1, 2, 4, ho c 8 Number ton, cc nh d ng d li u byte ki u s c thi t l p trong Control Panel. D li u ki u Date v Time. Cc nh d ng c a d li u Date/Time 8 byte Date/Time c thi t l p trong Control Panel. Currency Ki u ti n t , m c nh l $. 8 byte Access s t ng tng tu n t ho c ng u nhin khi m t m u AutoNumber 4 byte tin m i c t o, khng th xa, s a. Ki u lu n l (Boolean). Ch Yes/no ch p nh n d li u c gi tr 1bit Yes/No, True/False, On/Off D li u l cc i t ng c OLE Object T i a 1 GB t o t cc ph n m m khc. HyperLink D li u c a field l cc link. Lookup Wizard khng ph i l ki u d li u, m l ch c nng Lookup t o m t danh sch m gi tr Wizard c a n c nh p b ng tay ho c c tham chi u t m t b ng khc trong c s d li u. Attachmentnh km d li u t cc chng trnh khc, nhng b n khng th nh p vn b n ho c d li u s .

Text

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thay i nh ng nh d ng m c nh c a cc ki u d li u trong mi tr ng Window, ch n Start Control Panel Regional and Language Customize. Tab Numbers thay i nh d ng s nh d u th p phn, phn cch hng ngn Tab Date/Time thay i nh d ng ngy/gi . Tab Currency thay i n v ti n t .

2.5. Cc thu c tnh c a Field: 2.5.1. Field Size:Quy nh kch th c c a field, tu thu c vo ki u d li u. Ch c hi u l c v i cc Field c ki u l Text ho c Number. D li u ki u text: gi i h n kch th c t 0- 255 k t , m c nh l 50 k t . D li u ki u Memo: gi i h n kch th c t 0- 65.535 k t . i v i ki u d li u Number: ki u Number bao g m m t s ki u con, gi i h n kch th c ki u Number chnh l xc nh ki u con. Field size Mi n gi tr S l t i a Byte 0- 255 0 Integer -32768- 32767 0 Long integer - 214783648 214783647 0 38 38 Single -3.410 - 3.410 7 308 308 Double -1.7910 -1.7910 15 28 28 Decimal -10 -1 10 -1 20

2.5.2. Decimal Places:Quy nh s ch s th p phn (ch s d ng trong tr ng h p s c d ng single, double). i v i ki u Currency, Fixed, Percent lun lun decimal places l 2.-23-

Gio trnh Access

Trung tm Tin h c

2.5.3. Format:Quy nh d ng hi n th c a d li u trn mn hnh ho c ra my in, ph thu c vo ki u d li u. C th ch n cc nh d ng do Access cung c p s n ho c t o m t chu i k t nh d ng ring. a) nh d ng ki u d li u Text Cc k t nh d ng ki u d li u Text K t nh d ng Tc d ng@ > < chu i k t \ [Black] [White] [Red] [Green] [Blue] [Yellow] [Magenta] [Cyan] Chu i k t i ton b k t ra ch hoa i ton b k t ra ch th ng Chu i k t gi a 2 d u nhy K t n m sau d u \ Mu (k hi u mu theo sau m t trong cc k t nh d ng chu i pha trn)

V d : nh d ng@@@-@@-@@@ > D li u ghi t ph i sang tri. ! K t theo sau d u \ s c a th ng vo d \ li u Password Nh p d li u ki u m t kh u (ch hi n th d u *) L ? A a & C V d : Input Mask > L0L0L0 >L