Giáo trình thực hành SQL trần nguyên phong

SQL ( Structured Querry Language) là ngôn ngữ được sử dụng cho các hệ quản trị CSDL quan hệ. Ngôn ngữ SQL chuẩn được đưa ra bởi ANSI ( American National Standards Institute) và ISO ( International Standards Organization) với phiên bản mới nhất hiện nay là phiên bản SQL_ 92 ( phiên bản được đưa ra năm 1992). Mặc dù có nhiều ngôn ngữ khác nhau được đưa ra các hệ quản trị CSDL quan hệ....

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null constraint check_dienthoai check (dienthoai like '[0-9][0-9][0-9] [0-9][0-9] [0-9]') ) D DD D 5DQJEXF'()$8/7 5DQJEXÔF'()$8/7ÔFVGXÊQJTXLQKJLDWUPÊFQKFKRPÔWFÔW *LDWUQD\VHWÊÔQJÔFJDQFKRFÔWQD\NKLQJLVGXÊQJEVXQJPÔWEDQJKL PDNKQJFKQKJLDWUFKRFÔW7UQPĂLFÔWFKFRWKFRQKLXQKÂWPÔWUDQJ EXÔF'()$8/7WFODFKFRWKFRWÂLDPÔWJLDWUPÊFQK j NKDL EDR PÔW JLD WU PÊF QK FKR PÔW FÔW WD FK QK PÔW UDQJ EXÔF '()$8/7FKRFÔWEQJFDFKVGXÊQJFXSKDSVDX [CONSTRAINT constraint_name] DEFAULT {const_expression nonarguments_function NULL} 9 GX &X OÊQK GL \ FK QK JLD WU PÊF QK OD NKQJ ELÂW FKR FÔW ',$&+,WURQJEDQJ1+$19,(1YGXÊ CREATE TABLE nhanvien ( manv char(10) not null, hoten char(30) not null, ngaysinh datetime null, diachi char(50) default 'khọng bióỳt', dienthoai char(6) null ) D DD D 5DQJEXF35,0$5<.(< muYGXÊQD\FKXQJWLNKQJÊWWQFKRUDQJEXÔF'()$8/7.KLRKÊTXDQWU&6'/VHWÊÔQJÊWWQ FKRUDQJEXÔFQD\7X\QKLQGĂGDQJFKRYLÊFTXDQWUEDÊQQQÊWWQFKRFDFUDQJEXÔF Tráön Nguyãn Phong 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ODP¤WW£SK¤SWKDLF¤WWUOQED£QSKDLFKQKGDQKVDFKFDFF¤WVGX£QJUDQJ EX¤FPFEDQJ 9GX WD£REDQJ1+$19,(1YLNKRDFKQKOD0$19 CREATE TABLE nhanvien ( manv char(10) primary key, hoten char(30) not null, ngaysinh datetime null, diachi char(50) null, dienthoai char(6) null ) FXO£QKWUQFRWK YL¢WQKVDX CREATE TABLE nhanvien ( manv char(10) not null, hoten char(30) not null, ngaysinh datetime null, diachi char(50) null, dienthoai char(6) null constraint pk_nv primary key(manv) ) Giaùo trỗnh thổỷc haỡnh SQL 7UDQJ D 5DQJEXF81,48( 7KD\YVGXÊQJNKRDFKQKEDÊQFRWKVGXÊQJUDQJEXÔF81,48(DP EDRWQKWRDQYHÊQWKÊFWK6GXÊQJUDQJEXÔF81,48(WUQPÔWKD\QKLXFÔWEW EXÔFFDFJLDWUGOLÊXWUQPÔWKD\QKLXFÔWQD\NKQJÔFWUXQJOÊSQKDXj NKDLEDRPÔWUDQJEXÔF81,48(EDÊQVGXÊQJFXSKDSOÊQKVDX\ [CONSTRAINT constraint_name] UNIQUE [CLUSTERED | NONCLUSTERED] [colname1 [,colname2 [ .,colname16]])] D 5DQJEXF)25(,*1.(< &DFEDQJEQWURQJPÔW&6'/WKQJFRPÂLTXDQKÊYLQKDX&DFPÂLTXDQ KÊQD\ÔF[DFQKGÊDWUQWQKEQJQKDXJLDPÔWKD\QKLXWUQJFXDEDQJ QD\YLPÔWKD\QKLXWUQJFXDEDQJNKDF1ÂXPÔWKD\QKLXFÔWQDRRFXDPÔW EDQJFRJLDWUÔF[DFQKWPÔWKD\QKLXWUQJNKRDFXDEDQJNKDFWKFDF FÔWRÔFJRÔLODFRUDQJEXÔFNKRDQJRDÊLIRUHLJQNH\&DFUDQJEXÔF)25(,*1 .(<ÔFVGXÊQJNÂWKÔSYLFDFUDQJEXÔF35,0$5<.(<YD81,48(QKP DPEDRWQKWRDQYHÊQWKDPFKLÂXJLDFDFEDQJÔFFKQK jNKDLEDRNKRDQJRDÊLEDÊQVGXÊQJFXSKDSOÊQKQKVDX [CONSTRAINT constraint_name ] [FOREIGN KEY (colname [,colname2 [ .,colname16]])] REFERENCES reference_table [(ref_colname [,ref_colname2 [ .,ref_colname 16]])] 9 GX 7DÊR KDL EDQJ 1+$19,(10$19 +27(1 1*$<6,1+ ',$&+, ',(17+2$,0$'9YD'219,0$'97(1'9WKHRKQKGL\ CREATE TABLE donvi ( 1+$19,(1 0$19 +27(1 1*$<6,1+ ',$&+, ',(17+2$, 0$'9 '219, 0$'9 7(1'9 +QK Tráön Nguyãn Phong madv char(2) primary key, tendv char(20) not null ) CREATE TABLE nhanvien ( manv char(10) primary key, hoten char(20) not null, ngaysinh datetime null, diachi char(50) default 'khong biet', dienthoai char(6) check(dienthoai like '[0-9][0-9][0-9] [0-9][0-9][0-9]'), madv char(2) foreign key(madv) references donvi(madv) ) 6DLEDQJ 6DXNKLDWD£REDQJED£QFRWK WL¢QKDQKVD LF¢XWUXFKD\WKX¤FWQKFXD EDQJQKE VXQJF¤WE VXQJNKRDWKD\ LFDFUDQJEX¤Fj FRWK VXD L EDQJED£QVGX£QJFXO£QK$/7(5FRFXSKDSQKVDX ALTER TABLE table_name [ADD {col_name column_properties [column_constraints]  [[,]table_constraint ] } [,{next_col_name|next_table_constraint}] .] [DROP [CONSTRAINT] constraint_name1 [, constraint_name2] .] 9GX 7D£RP¤WUDQJEX¤FFKREDQJ'219,WUQF¤W0$'9TXLQKPDQY SKDLFRGD£QJKDLFKV¢YGX£ ALTER TABLE donvi ADD CONSTRAINT check_madv CHECK (madv LIKE ‘[0-9][0-9]’) Giaùo trỗnh thổỷc haỡnh SQL 7UDQJ &KPXFLQGH[ &DFFKPXÊFÔFVGXÊQJQKPKĂWUÔYLÊFWUX\FÊSÂQFDFGRQJGOLÊXÔF QKDQKFKRQJGÊDWUQFDFJLDWUFXDPÔWKD\QKLXFÔW&KPXÊFÔFFKLDUDODPKDL ORDÊLFKPXÊF WXÊ QKRPFOXVWHUHG LQGH[YD FKPXÊF NKQJ WXÊ QKRP QRQFOXVWHUHG LQGH[ 0ÔWFKPXÊFWXÊQKRPODPÔWFKPXÊFPDWURQJRWKWÊORJLFFXDFDFNKRDWQJ WÊQKWKWÊYÊWO\FXDFDFGRQJWQJQJWQWDÊLWURQJEDQJ0ÔWEDQJFKFR WKFRWÂLDPÔWFKPXÊFWXÊQKRP 0ÔWFKPXÊFNKQJWXÊKRPODPÔWFKPXÊFPDWURQJRWKWÊORJLFFXDFDFNKRD NKQJQKWKWÊYÊWO\FXDFDFGRQJWURQJEDQJ&DFFKPXÊFWXÊQKRPKĂWUÔYLÊF WUX\FÊSÂQFDFGRQJGOLÊXQKDQKKQQKLXVRYLFDFFKPXÊFNKQJWXÊQKRP .KLWDNKDLEDRPÔWNKRDFKQKKD\NKRD81,48(WUQPÔWKD\QKLXFÔWQDRR FXDEDQJKÊTXDQWU&6'/VHWÊÔQJWDÊRFKPXÊFWUQFDFFÔWR%DÊQFRWKWDÊR WKPFDFFKPXÊFNKDFEQJFDFKVGXÊQJFXOÊQKFRFXSKDSQKVDX CREATE [CLUSTEREDNONCLUSTERED] INDEX index_name ON table_name(column_name [, column_name] .) 9GX &XOÊQKGL\VHWDÊRPÔWFKPXÊFNKQJWXÊQKRPWUQFÔW0$'9FXD EDQJ1+$19,(1 CREATE NONCLUSTERED INDEX idx_nhanvien_madv ON nhanvien(madv) .KXQJQKQ9LHZ 0ÔWNKXQJQKQFRWKFRLQKODPÔWeEDQJDRfFRQÔLGXQJÔF[DFQKW PÔWWUX\YÂQ0ÔWWUX\YÂQTXHU\ODPÔWWÊSFDFFKGĂQLQVWUXFWLRQQKPWUX\ [XÂWYDKLQWKGOLÊXWFDFEDQJWURQJ&6'/&DFWUX\YÂQÔFWKÊFKLÊQEQJ FDFKVGXÊQJFXOÊQK6(/(&7ÔFFÊSÂQWURQJFKQJ 0ÔWNKXQJQKQWURQJJLÂQJQKPÔWEDQJYLPÔWWÊRFDFWQFÔWYDFDFGRQJ 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.KQJWK [\G£QJFKPX£FFKRNKXQJQKQ • 7URQJFXO£QK&5($7(9,(:NKQJFQWKL¢WSKDLFKQKWQF¤W7QFXD FDFF¤WFXQJQKNL XGOL£XFXDFKXQJVHWQJQJYLFDFF¤WWURQJGDQKVDFK FKR¤QFXDFXO£QK6(/(&7 • %D£QSKDL[DFQKWQF¤WWURQJFXO£QK&5($7(9,(:WURQJFDFWUQJK¤S VDX − 0¡LF¤WFXDNKXQJQKQ¤FSKDWVLQKWP¤WEL XWKFV¢KR¤FP¤WKDPFDL VQKD\P¤WKQJ − +DLKD\QKLXF¤WFXDNKXQJQKQFRWUXQJWQ − %D£QPX¢QWKD\ LWQF¤WWURQJNKXQJQKQNKDFYLWQF¤WFXDEDQJFV 9GX &XO£QKGL\VHEO¡LGRWQFXDF¤WWKNKQJ[DFQK¤F CREATE VIEW thongtin_nv AS SELECT manv,hoten,datediff(year,ngaysinh,getdate()),tendv FROM nhanvien,donvi WHERE nhanvien.madv=donvi.madv j FXO£QKWUQFRWK WK£FKL£Q¤FED£QSKDL£WWQFKRFDFF¤WFXDNKXQJQKQ QKVDX CREATE VIEW thongtin_nv(manv,hoten,tuoi,donvi) . sau: Họ và tên Hệ số lương ---------------- -------------- ------------- Trần Nguyên Phong Hệ số lương là : 1.92 Lê Hoài Nam Hệ số lương là : 1.86 Nguyễn Hữu. dụng UNION với các giao tác SQL khác Các nguyên tắc sau phải được tuân theo khi sử dụng phép hợp với các câu lệnh giao tác SQL khác: Truy vấn đầu tiên