What is the by statement in SAS?
The BY statement is used in SAS to instruct the DATA step or procedures to process dataset observations in groups, rather than singly. It can be used whenever SAS data is ordered, or can be accessed in order through a SAS dataset index.
What is by in SAS with example?
Controls the operation of a SET, MERGE, MODIFY, or UPDATE statement in the DATA step and sets up special grouping variables….BY Statement.
| Valid in: | DATA step or PROC step |
|---|---|
| Type: | Declarative |
| See: | Definitions for BY-Group Processing in SAS Programmer’s Guide: Essentials |
What is by Group Processing in SAS?
With BY-group processing, SAS selects the observations from the data sets according to the values of the BY variable or variables. After processing all the observations from one BY group, SAS expects the next observation to be from the next BY group.
What does set command do in SAS?
The function of the SET statement is to process existing SAS data sets as input for a DATA step. With no options specified, the SAS System sequentially reads each observation in the named data sets, one observation at a time, until there are no further observations to process.
How does merge work in SAS?
To merge two or more data sets in SAS, you must first sort both data sets by a shared variable upon which the merging will be based, and then use the MERGE statement in your DATA statement.
How do you retain in SAS?
The RETAIN statement simply copies retaining values by telling the SAS not to reset the variables to missing at the beginning of each iteration of the DATA step. If you would not use retain statement then SAS would return missing at the beginning of each iteration. The retain statement keeps the value once assigned.
How do you rank in SAS?
First, we order our data set by the group (class) and then by the variable to rank (score). With the BY statement, the FIRST keyword, and a simple IF-THEN statement we assign a value of 1 to our new variable rank if SAS processes a row with a new class.
How does SAS DATA step work?
The DATA step consists of a group of SAS statements that begins with a DATA statement. The DATA statement begins the process of building a SAS data set and names the data set. The statements that make up the DATA step are compiled, and the syntax is checked. If the syntax is correct, then the statements are executed.
How do you write DATA in SAS?
Begin the DATA step and create a SAS data set called WEIGHT. Specify the external file that contains your data. Read a record and assign values to three variables. Calculate a value for variable WeightLoss.
How do you join tables in SAS?
Joining Tables Manually
- If the Tables and Joins window is not already open, click Join Tables in the Query Builder window.
- Drag the column name from the table that you want to join to the corresponding column in the table to which you want to join it.
- Select the join type that you want to use.