PROC SQL - UPDATE

[Abhau]

i'm confusing in this question , and how to subtract ?
please help me out.

Run a single SQL program to update the values of variables. Add 5 more with weight if Type is Hamburger and subtract 100 from Calories. 

[mkeintz]

Re: "subtract":

In your select expression, you need to reduce the value of the calories field by 100.   I.e., you are being asked not only to list a bunch of fields from a table, but also to introduce a mathematical expression that would change the value of calories.

[Abhau]

yes exactly , please help me out

[Abhau]

This is my assignment , and this the question which i have , data sets i've by the name of junk food in that 8 variables , only the thing is , i've to update weight variable,as well as i've to subtract 100 from calories , in type variable Hamburger. please give some solution . sir

[Tom]

---

@Abhau wrote:

i'm confusing in this question , and how to subtract ?
please help me out.

Run a single SQL program to update the values of variables. Add 5 more with weight if Type is Hamburger and subtract 100 from Calories. 

---

What I normally do on a test where the question is written in a confusing way is make an assumption about what they mean and explain clearly what question I am actually going to answer and then answer the clarified question.

So in this case if the question means:

Given a dataset name FOOD with character variable TYPE and numeric variables WEIGHT and CALORIES write a program using the SQL UPDATE statement that will for observations that have TYPE equal to 'Hamburger' change the value of WEIGHT to have 5 more (assuming that units are the same) and also update the value of CALORIES to have 100 less calories (assuming that values are already in calories).

Then an answer might look like:

proc sql;
update FOOD
  set weight=weight+5
    , calories=calories-100
  where type='Hamburger'
;
quit;

[Abhau]

this is the error which i'm getting , 
you gave me the code i used

ERROR 73-322: Expecting an =.

ERROR 76-322: Syntax error, statement will be ignored.

64 , calories=calories-100
65 where type='Hamburger';
66 quit;
NOTE: The SAS System stopped processing this step because of errors.
NOTE: PROCEDURE SQL used (Total process time):
real time 0.01 seconds
cpu time 0.01 seconds

[Tom · Accepted solution]

The code works for me. You didn't include enough of your SAS log for us to see what error you might have made.

data food;
  length type $20 weight calories 8;
  input type weight calories ;
cards;
Hamburger 20 500
Hamburger 24 600
Chips 5 1000
;

proc print data=food;
 title 'BEFORE';
run;

proc sql;
update FOOD
  set weight=weight+5
    , calories=calories-100
  where type='Hamburger'
;
quit;

proc print data=food;
 title 'AFTER';
run;

BEFORE  

Obs    type         weight    calories

 1     Hamburger      20         500
 2     Hamburger      24         600
 3     Chips           5        1000

AFTER

Obs    type         weight    calories

 1     Hamburger      25         400
 2     Hamburger      29         500
 3     Chips           5        1000

[Abhau]

wow thank you