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转自：Evernory查询时生成序号SELECT (SELECT Count([xlh].[aa]) AS AutoNum FROM xlh WHERE (((xlh.aa)<=xlh_Alias.aa));) AS 序号, xlh.aaFROM xlh AS xlh_Alias INNER JOIN xlh ON xlh_Alias.aa=xlh.aaORDER BY xlh.aa;多表sql查询SELECT test.aa AS 第一个字段, test1.bb AS 第二个字段, test1.ccFROM test, test1WHERE test.aa=test1.aa;多表sql 阅读全文
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转自:万一//单字符 Char、AnsiChar (在目前版本(2007)中, 它们是一回事, 只有 1 字节大小)var c: Char; {Char 类型的取值范围是: #0..#255, 用十六进制表示是: #$0..#$FF}begin {用十进制方式赋值:} c := #65; ShowMessage(c); {A} {用十六进制方式赋值:} c := #$41; ShowMessage(c); {A} {用 Chr 函数代替 # 符号} c := Chr(65); ShowMessage(c); {A} c := Chr($41); ShowMessage(c); {A} {Cha 阅读全文
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转自：万一//最常用的 stringvar str: string; {定义}begin str := '万一'; {赋值} ShowMessage(IntToStr(Length(str))); {长度是: 4}end;//长字符串 AnsiString; 在当前版本(2007)中的默认状态下, String 就是 AnsiStringvar str: AnsiString;begin str := '万一'; ShowMessage(IntToStr(Length(str))); {长度是: 4}end;//宽字符串 WideString (效率不及 Ans 阅读全文
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Lesson Twenty-one Mad or notAeroplanes are slowly drving me mad. I live near an airport and passing planesCan be heard night and day. The airport was built years ago, but for some reasonIt could not be used then. Last year, however, it came into use. Over a hundredPeople must have been driven away f 阅读全文
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pl/sql语言是oracle对关系数据库语言sql的过程化扩充。一、顺序结构 1 declare 2 v_student students%rowType; 3 begin 4 select * into v_student 5 from students 6 where student_id = 10213; 7 dbms_output.put_line('姓名：'|| v_student.name); 8 dbms_output.put_line('性别：'|| v_student.sex); 9 dbms_output.put_line('专业： 阅读全文