Add rows to data set

[Ronein]

Hello

Lets say that I have data set A and every day I create another data set called B and then I want to add the rows of B to A.

I want to show 2 ways and ask which way is better ?

/*Way1*/
Data A;
SET A B;
Run;
/*Way2*/
Data tempTbl;
SET A;
Run;
Proc delete data=A;Run;
Data A;
SET tempTbl B;
Run;

[ballardw · Accepted solution]

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@Ronein wrote:

Hello

Lets say that I have data set A and every day I create another data set called B and then I want to add the rows of B to A.

I want to show 2 ways and ask which way is better ?

/*Way1*/
Data A;
SET A B;
Run;
/*Way2*/
Data tempTbl;
SET A;
Run;
Proc delete data=A;Run;
Data A;
SET tempTbl B;
Run;

---

Proc append if the data sets have the same variables with the same lengths for character variables would be the better choice.

Anything involving a data step reads each and every record. Which means your "Set A B"; runs slower and slower as A bets bigger.

Proc Append works a bit differently and will typically run much faster for this type of activity.

If the variables are not the same then the first way would be more efficient in resources.