11 2014 档案
摘要:1:防止不必要的排序下面四种方式可以防止排序的进行1.1:BY-group processing with an index to avoid a sort在以下情况下,by语句不会用索引the BY statement includes theDESCENDING or NOTSORTED o...
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摘要:1:where和If最本质的区别,以及一些小的区别1.1:The WHERE statement examines what is in the input page buffer and selectsobservations before they are loaded in the progr...
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摘要:Understanding the Global Macro Symbol Table Detail •The macro processor creates the global macro symbol table at the start of a SAS session. Four...
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摘要:transpose基本语法Note: If output-data-set does not exist, PROC TRANSPOSE creates it by using theDATA n naming convention. Note: If you omit the VAR stat...
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摘要:CPU time:the amount of time the central processing unit (CPU) uses toperform requested tasks such as calculations, reading and writingdata, conditiona...
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摘要:SAS读取小工具 1:Column-Pointer Controls @n : move the pointer to the n column in the input buffer. +n : move the pointer forward n columns in the i...
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摘要:1:在程序运行中进行宏定义CALL routines that enable you to transfer information between an executing DATA step and the macro processor.You can use the SYMPUT routi...
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摘要:1:Proc sql中的选项1.1:INOBS/OUTOBS=这个选项意思在前面的随笔中已说过,就INOBS这里有个例子这里的INOBS=5是针对于两张表分别读入5个,而不是一共读入五个1.2:NUMBER/NONUMBER效果如下1.3:Double/NoDoubleDouble Spacing ...
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摘要:什么是视图?视图是一系列的查询语句,在使用时被执行,用来从其他的数据集或视图中获取想要的子集(subset)或者超集(superset)。The view contains only the logicfor accessing the data, not the data itself视图能用在哪...
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摘要:update / insert into后面不需要加table关键字1:三种建表方式建表只会在库中建立好表格并在日志中显示,并不会有输出。1.1:自己定义列来建立一张空表column-specification = column-define + column-constriants + MESSA...
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摘要:SQL进行纵向操作的基本语法proc sql;select *from table1set-operator select *from table2set-operator select *from table3;1:几种set操作符Except、Intersect、Union、OuterJoi...
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摘要:1.1:Specifying Column Formats and Labels (SAS enhancements.)proc sql outobs=15; title 'Current Bonus Information'; title2 'Employees with Sa...
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摘要:SAS macro variables 1. enable you to substitute text in your SAS programs(替代作用,和c++的 #define 差不多) 2. When you reference a macro variable in a SAS pr...
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摘要:index : 字符函数 数值函数 日期含糊 SCL函数 特殊函数/**********************字符函数******************************/Compress();功能:消除或保留指定的字符I or i: ignores the case of the cha...
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摘要:Sas proc sql与寻常sas语句的的不同之处1:The PROC SQL step does not require a RUN statement. PROC SQL executes each query automatically2:Unlike many other SAS pr...
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摘要:1:获取数据集前几行观测proc sql outobs=5; *outobs选项只限制显示的行数,并不限制读入的行数. inobs=选项可以限制读入的行数; select * from sashelp.class;quit;data res; set sashelp.cl...
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