PROC SQL by Example: Using SQL within SAS
In PROC SQL by means of instance: utilizing SQL inside SAS, writer Howard Schreier illustrates using PROC SQL within the context of the SAS information step and different SAS strategies (such as type, FREQ, capacity, precis, APPEND, DATASETS, and TRANSPOSE) whose performance overlaps and enhances that of SQL.
utilizing a side-by-side technique, this concise reference consultant comprises many widely defined examples exhibiting an identical information step and SQL code, permitting SAS clients to exploit current SAS talents and information whereas studying approximately SQL. Discussions hide the variations among SQL and the knowledge step in addition to events the place SQL and the information step are used jointly to profit from the strengths of every.
themes addressed comprise operating with joins and merges; utilizing subqueries; figuring out set operators; utilizing the Macro Facility with PROC SQL; holding tables; operating with perspectives; utilizing PROC SQL as a document generator; and extra.
this article is perfect for SAS programmers looking to upload PROC SQL to their SAS toolkits in addition to SQL programmers striving to raised combine the SAS info step and SQL.
detailed all the columns explicitly. either the SQL correct subscribe to and the information step code proven previous to produce a similar desk (shown in show 4-10). convey 4-10 COMBINED_RIGHT Key Value1 Value2 A eleven 21 C . 23 fit MERGE as opposed to internal sign up for frequently it truly is acceptable to shed nonmatching rows from either resources. In SQL, this can be often called an internal sign up for. So in fact we use internal in entrance of subscribe to, as in: PROC SQL; make a choice from ON ; give up; * u1 internal subscribe to u2 u1.key = u2.key Chapter 4:.
this occurs as the information step doesn't do its reinitialization processing till the start of a brand new through workforce. info step programmers mostly stay away from this example (repeating keys in additional than one resource info set) since it frequently doesn't produce precious or acceptable effects. Chapter four: Joins seventy one subsequent, we practice an internal sign up for of those comparable tables: PROC SQL; choose from ON ; give up; * m1 internal sign up for m2 m1.key = m2.key This yields: Key Value1 Key Value2.
SET moregirls; the place PUT(fname,$classgirls.)='Y'; RUN; The output is proven in show 5-3. show 5-3 ALREADY FName Jane Age 12 certainly, Jane is the one identify in universal. realize that we needed to run SAS steps (a information step and a PROC layout step) simply to arrange, sooner than we even grew to become to coding our the place assertion. by contrast, SQL can reference the search for desk without delay in the the place situation and with no such preprocessing. The EXISTS situation SQL presents a situation (similar to an.
desk choose from the place ORDER by means of ; surrender; one AS identify as FName, weight, age sashelp.class age<13 and LENGTH(name) GE five age, RANUNI(1) AS identify as FName, age, top sashelp.class age<13 and LENGTH(name) LE five age, RANUNI(2) we get ONE (see convey 6-1): convey 6-1 ONE FName Weight Age Thomas 85.0 eleven Joyce 50.5 eleven James 83.0 12 Robert 128.0 12 Louise 77.0 12 and (see convey 6-2). express 6-2 FName Age top Joyce eleven 51.3 James 12 57.3 John 12 59.0 Jane.
CREATE desk choose between UNION choose between ; surrender; union AS * abc * ab the result's the desk noticeable in show 6-15. show 6-15 UNION (from PROC SQL) identity Code 1 aa 1 bb 1 cc As acknowledged past, within the absence of the ALL alternative, the replica rows are purged. This procedure is played after the rows from the 2 assets are pooled (if it have been played ahead of, there may nonetheless be pairs of exact rows within the result). The UNION operator is commutative, which means that the implications usually are not.