SAS/ACCESS 9.2 for Relational Databases: Reference, Fourth Edition

816 Reducing Workload on Teradata by Sampling 4 Chapter 28This example removes the PROC SORT statement shown in the previous example. Itinstead uses a BY clause with a VAR clause with PROC PRINT. The BY clause returnsTeradata rows ordered by the INCOME column.libname sortprt teradata user=testuser password=testpass;proc print data=sortprt.salaries;var income;by income;Reducing Workload on Teradata by SamplingThe OBS= option triggers SAS/ACCESS to add a SAMPLE clause to generated SQL.In this example, 10 rows are printed from dbc.ChildrenX:Libname tra teradata user=sasdxs pass=******Proc print data=tra.ChildrenX (obs=10);run;database=dbc;The SQL passed to Teradata is:SELECT "Child","Parent" FROM "ChildrenX" SAMPLE 10Especially against large Teradata tables, small values for OBS= reduce workload andspool space consumption on Teradata and your queries complete much sooner. See theSAMPLE clause in your Teradata documentation for further information.Deploying and Using SAS Formats in TeradataUsing SAS FormatsSAS formats are basically mapping functions that change an element of data fromone format to another. For example, some SAS formats change numeric values tovarious currency formats or date-and-time formats.SAS supplies many formats. You can also use the SAS FORMAT procedure to definecustom formats that replace raw data values with formatted character values. Forexample, this PROC FORMAT code creates a custom format called $REGION thatmaps ZIP codes to geographic regions.proc format;value $region’02129’, ’03755’, ’10005’ = ’Northeast’’27513’, ’27511’, ’27705’ = ’Southeast’’92173’, ’97214’, ’94105’ = ’Pacific’;run;SAS programs, including in-database procedures, frequently use both user-definedformats and formats that SAS supplies. Although they are referenced in numerousways, using the PUT function in the SQL procedure is of particular interest for SASIn-Database processing.The PUT function takes a format reference and a data item as input and returns aformatted value. This SQL procedure query uses the PUT function to summarize salesby region from a table of all customers: