DATA Step Partitioning and Sorting in CAS

This script configures a CAS session and loads the SASHELP.BASEBALL table into CAS memory. It demonstrates the use of dataset options 'partition=' and 'orderby=' to physically organize data on compute nodes, which optimizes subsequent group processing (BY). A second DATA Step illustrates this usage with a cumulative counter calculation (RETAIN) per team.

Data Analysis

Type : SASHELP

Source data comes from the standard SASHELP library (BASEBALL table).

1 Code Block

CONFIGURATION

Explanation :
CAS connection initialization. Creates a 'CASWORK' libref pointing to the 'casuser' caslib, sets it as the default library (USER), and assigns all visible caslibs.

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1	LIBNAME CASWORK cas caslib=casuser;
2	options USER = CASWORK;
3	caslib _all_ assign;
4	%put &_sessref_;

2 Code Block

DATA STEP Data

Explanation :
Creation of a partitioned and sorted CAS table. The 'partition' option distributes data by division and row order, and 'orderby' ensures sorting within partitions, optimizing future access.

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1	DATA caswork.baseball(partition=(div row_order) orderby=(div row_order));
2	SET sashelp.baseball;
3	row_order = _n_;
4	RUN;

3 Code Block

DATA STEP Data

Explanation :
Data processing by group (BY DIV TEAM). Calculates a sequential counter for each team using the RETAIN statement and the automatic variable first.team.

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1	DATA caswork.baseball2;
2	SET caswork.baseball;
3	retain count;
4	BY DIV TEAM;
5	IF first.team THEN
6	count=0;
7	count+1;
8	RUN;

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