sas数据操作-3

data stock(index=(partno));
   input PARTNO $ DESC $ INSTOCK @17 
         RECDATE date7. @25 PRICE;
   format  recdate date7.;
   datalines;
K89R seal   34  27jul95 245.00
M4J7 sander 98  20jun95 45.88
LK43 filter 121 19may96 10.99
MN21 brace 43   10aug96 27.87
BC85 clamp 80   16aug96 9.55
NCF3 valve 198  20mar96 24.50
KJ66 cutter 6   18jun96 19.77
UYN7 rod  211   09sep96 11.55
JD03 switch 383 09jan97 13.99
BV1E timer 26   03jan97 34.50
;
run;

/*直接改变所有的recdate变量观测值,可以不用任何更新数据集*/

data stock;
modify stock;
recdate=today();
run;
proc print data=stock noobs;
title ‘INVTY.STOCK‘;
run;

/*用更新数据集更新主数据集，使用匹配访问，更新数据集放在主数据集后面*/

data stock;
modify stock addinv;
by partno;
RECDATE=today();
INSTOCK=instock+nwstock;
if _iorc_=0 then replace;
run;
proc print data=stock noobs;
title ‘STOCK‘;
run;

data newp;
   input TOOL_OBS NEWP;
   datalines;
 1 251.00
 2 49.33
 3 12.32
 4 30.00
 5 15.00
 6 25.75
 7 22.00
 8 14.00
 9 14.32
10 35.00
;
/*通过观测序号来访问，先set数据集再进行改变*/

data stock;
set newp;
modify stock point=tool_obs nobs=max_obs;
price=newp;
recdate = today();
run;

/*通过索引进行访问，先set数据集再进行改变*/

data stock;
set addinv;
modify stock key=partno;
INSTOCK=instock+nwstock;
RECDATE=today();
if _iorc_=0 then replace;
run;
proc print data=stock noobs;
title ‘INVTY.STOCK‘;
run;

 /*对于更新数据集有重复值的情况*/

data newinv;
   input PARTNO $ NWSTOCK;
   datalines;
K89R 55
M4J7 21
M4J7 26
LK43 43
MN21 73
BC85 57
NCF3 90
KJ66 2
UYN7 108
JD03 55
BV1E 27
;

data stock;
   set newinv;
   modify invty.stock key=partno / unique;  /*使用unique则会对m4j7的值进行累加，不用就只会加第一个*/
   INSTOCK=instock+nwstock;
   RECDATE=today();
   if _iorc_=0 then replace;
run; 
proc print data=stock noobs;
   title ‘Results of Using the UNIQUE Option‘;
run;