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| SPD Engine Data Set Options |
BYNOEQUALS= Data Set Option
Specifies whether the output order of data set observations that have identical values for the BY variable is guaranteed to be in the data set order.
| Valid in: | DATA step and PROC step |
| Used with: | BYSORT=YES data set option |
| Default: | NO |
| Syntax | |
| Details | |
| Examples | |
| Example 1: BYNOEQUALS=YES | |
| Example 2: BYNOEQUALS=NO | |
Syntax |
| BYNOEQUALS=YES | NO |
- YES
-
does not guarantee that the output order of data set observations that have identical values for the BY variable is in data set order.
- NO
-
guarantees that the output order of data set observations that have identical values for the BY variable is in data set order.
| Details |
When a group of observations that have identical values for the BY statement is output, the order of the observations in the output is the same as the data set order because the default is BYNOEQUALS=NO. By specifying YES, the processing time is decreased, but the observations are not guaranteed to be output in the data set order.
The data set or LIBNAME option BYSORT= must be YES (the default) because the BYNOEQUALS= option has no effect when BYSORT=NO.
The following table shows when the SPD Engine preserves physical order in the output:
| Condition: | Data Set Order Preserved? |
|---|---|
| If BY is present | YES (BYNOEQUALS=NO and BYSORT=YES by default) |
| If BY is present and BYNOEQUALS=YES | NO |
| If BY is present and BYSORT=NO | YES (because no automatic sort occurs) |
| If neither BY nor WHERE is present | YES |
| If WHERE is present | NO |
| Examples |
Example 1: BYNOEQUALS=YES
In the following example, the observations that have identical BY values on the key variable are output in unpredictable order because BYNOEQUALS=YES:
title 'With BYNOEQUALS=YES'; proc print data=tempdata.housreps(bynoequals=yes); by state; where state in ('CA' 'TX'); run;
The output is shown:
With BYNOEQUALS=YES
State=CA
Obs Representative District
26 Berman, Howard L. 26th
55 Calvert, Ken 43d
60 Capps, Lois 22d
76 Cardoza, Dennis 18th
22 Becerra, Xavier 30th
9 Baca, Joe 42d
80 Cox, Christopher 47th
38 Bono, Mary 44th
89 Cunningham, Randy "Duke" 50th
State=TX
Obs Representative District
87 Culberson, John Abney 7th
20 Barton, Joe 6th
75 Combest, Larry 19th
36 Bonilla, Henry 23d
8 Armey, Richard K. 26th
23 Bentsen, Ken 25th
44 Brady, Kevin 8th
Example 2: BYNOEQUALS=NO
The following example shows the output with BYNOEQUALS=NO:
title 'With BYNOEQUALS=NO'; proc print data=tempdata.housreps(bynoequals=no); by state; where state in ('CA' 'TX'); run;
The output is shown:
With BYNOEQUALS=NO
State=CA
Obs Representative District
9 Baca, Joe 42d
22 Becerra, Xavier 30th
26 Berman, Howard L. 26th
38 Bono, Mary 44th
55 Calvert, Ken 43d
60 Capps, Lois 22d
76 Cardoza, Dennis 18th
80 Cox, Christopher 47th
89 Cunningham, Randy "Duke" 50th
State=TX
Obs Representative District
8 Armey, Richard K. 26th
20 Barton, Joe 6th
23 Bentsen, Ken 25th
36 Bonilla, Henry 23d
44 Brady, Kevin 8th
75 Combest, Larry 19th
87 Culberson, John Abney 7th
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