Пример, для @ Lee
data have1;
attrib name length=$10 format=$10.;
name = "Anton Short";
run;
data have2;
attrib name length=$50 format=$50.;
name = "Pippy Longstocking of Stoyville";
run;
* column attributes such as format, informat and label of the selected columns
* in the result set are 'inherited' on a first found first kept order, dependent on
* the SQL join plan (i.e. the order of the tables as coded for the query);
proc sql;
create table want as
select name from have1 union
select name from have2
;
proc contents data=want varnum;
run;
Формат закорочен, чем Length , любой вывод более длинных значений будет обрезан на уровне данных.
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* attributes of columns can be reset,
* (cleared so as to be dealt with in default manners),
* without rewriting the entire data set;
proc datasets nolist lib=work;
modify want;
attrib name format=; * format= removes the format of a variable;
run;
proc contents data=want varnum;
run;
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