SAS Proc SQL to add a constant to a variable - sas

I have a SAS dataset with numeric variables to, from, and weight. Some of the observations have value 0 for weight. I need all the weight values to be positive, so I wish to simply add 1 to all weight values.
How can I do that using Proc SQL?
I have tried the following, but it doesn't work:
proc sql;
update mylib.mydata
set weight=weight+1;
quit;
The error is:
ERROR: A CURRENT-OF-CURSOR operation cannot be initiated because
the column "weight" cannot be used to uniquely identify a row
because of its data type.
Also, mylib refers to a Greenplum appliance. This might be the problem...

If you have the database permissions to update that table, you might want to use the SAS/Access pass-through facility. You will need to know the correct syntax for this to work. Here is a non-working example:
proc sql;
connect to greenplm as dbcon
(server=greenplum04 db=sample port=5432 user=gpusr1 password=gppwd1);
execute (
/* Native code goes here */
update sample.mydata
set weight=weight+1
) by dbcon;
quit;
The connection string would be the same as used on the LIBNAME that defined your "mylib' libref.
However, if you are really trying to create a SAS dataset (not update the real table), you can do that with a simple data step:
data mydata;
set mylib.mydata
weight = weight + 1;
run;
That will create a copy of the table that can be used with other SAS procedures.

Check out this note at prosgress.com. You probably need to add UPDATE_MULT_ROWS=YES to your library definition.

Related

SAS Proc format cntlin equivalent in Teradata

Is there an equivalent to the SAS format cntlin procedure in Teradata. I have a reference value table (code_value), which is used a lot and rather than doing many outer joins to the reference value table, I'd like to have a lookup function similar to the solution below in SAS. Any help is greatly appreciated.
data CodeValueFormat;
set grp.code_value (keep=code_value_id description);
fmtname = 'fmtCodeValue';
start = code_value_id;
label = description;
run;
proc format cntlin=work.codevalueformat;
run;
proc sql;
select foo_code_id format=fmtCodeValue.
from bar;
quit;
There is no way you can emulate SAS format cntlin procedure in Teradata or any other database other than using lookup tables. One way to avoid doing same joins again and again is to do index join. please look into below link to see whether this is what you want to do. https://info.teradata.com/HTMLPubs/DB_TTU_16_00/index.html#page/Database_Management%2FB035-1094-160K%2Fqiq1472240587768.html%23wwID0EFK1R
One another way is to maintain a denormalized table and do joins with your incremental/daily records in your staging area and then append this records to your final table

Filter a SAS dataset to contain only identifiers given in a list

I am working in SAS Enterprise guide and have a one column SAS table that contains unique identifiers (id_list).
I want to filter another SAS table to contain only observations that can be found in id_list.
My code so far is:
proc sql noprint;
CREATE TABLE test AS
SELECT *
FROM data_sample
WHERE id IN id_list
quit;
This code gives me the following errors:
Error 22-322: Syntax error, expecting on of the following: (, SELECT.
What am I doing wrong?
Thanks up front for the help.
You can't just give it the table name. You need to make a subquery that includes what variable you want it to read from ID_LIST.
CREATE TABLE test AS
SELECT *
FROM data_sample
WHERE id IN (select id from id_list)
;
You could use a join in proc sql but probably simpler to use a merge in a data step with an in= statement.
data want;
merge oneColData(in = A) otherData(in = B);
by id_list;
if A;
run;
You merge the two datasets together, and then using if A you only take the ID's that appear in the single column dataset. For this to work you have to merge on id_list which must be in both datasets, and both datasets must be sorted by id_list.
The problem with using a Data Step instead of a PROC SQL is that for the Data step the Data-set must be sorted on the variable used for the merge. If this is not yet the case, the complete Data-set must be sorted first.
If I have a very large SAS Data-set, which is not sorted on the variable to be merged, I have to sort it first (which can take quite some time). If I use the subquery in PROC SQL, I can read the Data-set selectively, so no sort is needed.
My bet is that PROC SQL is much faster for large Data-sets from which you want only a small subset.

Run Duration in SAS enterprise miner

I have the following problem. We have several streams in Enterprise Miner and we would like to be able to tell how long was each run. I have tried to create a macro that would save the start and end time/date but the problem is that global variables defined in a node, are not seen anymore in a subsequent node (so are global only inside a node, but not between nodes). How people usually solve the problem? Any idea or suggestion?
Thanks, Umberto
Just write out timestamps to log (EM should produce a global log in the same fashion that EG and DI do)
Either use:
data _null_;
datetime = datetime();
put datetime= datetime20.;
run;
or macro language:
%put EM node started at at %sysfunc(time(),timeampm.) on %sysfunc(date(),worddate.).;
with a higly customised message you have read the log in SAS looking for those strings using regex.
Solution 2:
Other option is to created a table in a library that is visible from EM and EG for example and have sql inserts at the beginning/end of your process.
proc sql;
create table EM_logger
(jobcode char(100),
timestamp num informat=datetime20. format=datetime20.);
quit;
proc sql;
insert into EM_logger values('Begining Linear Reg',%sysfunc(datetime()));
quit;
data w;
do i=1 to 10000000;
output;
end;
run;
proc sql;
insert into EM_logger values('End Linear Reg',%sysfunc(datetime()));
quit;
Table layout can be as complex as you want and as long as you can access it you can get your statistics.
Hope it helps

SAS : Select rows from a relationnal database

I work with SAS on a relationnal database that I can access with a libname odbc statement as below :
libname myDBMS odbc datasrc="myDBMS";
Say the database contains a table named 'myTable' with a numeric variable 'var_ex' which values can be 0,1 or . (missing). Now say I want to exclude all rows for which var_ex=1.
If I use the following :
DATA test1;
SET myDBMS.myTable; /* I call directly the table from the DBMS */
where var_ex NE 1;
run;
I don't get rows for which 'var_ex' is missing. Here is a screenshot of the log, with my actual data :
Whereas if I do the exact same thing after importing the table in the Work :
DATA myTable; /* I put myTable in the Work library */
SET myDBMS.myTable;
run;
DATA test2;
SET myTable; /* I call the table from the work */
where var_ex NE 1;
run;
I select rows for which 'var_ex' is 0 or missing, as intended. Here is a screenshot of the log, with my actual data :
The same happens if I use PROC SQL instead of a DATA step, or another NE-like.
I did some research and more or less understood here that unintended stuff like that can happen if you work directly on a DBMS table.
Does that mean is it simply not recommended to work with a DBMS table, and one has to import table locally as below before doing anything ?
DATA myTable; /* I put myTable in the Work library */
SET myDBMS.myTable;
run;
Or is there a proper way to manipulate such tables ?
The best way to test how SAS is translating the data step code into database code is through the sastrace system option. Before running code, try this:
options sastrace=',,,db' sastraceloc=saslog;
Then run your code tests. When you check the log, you will see precisely how SAS is translating the code (if it can at all). If it can't, you'll see,
ACCESS ENGINE: SQL statement was not passed to the DBMS, SAS will do the processing.
followed by a select * from table.
In general, if SAS cannot translate data step code into dbms-specific code, it will pull everything to locally manipulate the data. By viewing this output, you can determine precisely how to get the data step to translate into what you need.
If all else fails, you can use explicit SQL pass-through. The code in parentheses operates the same way as if you're running SQL directly from some other client.
proc sql;
connect to odbc(datasrc='source' user='username' pass='password');
create table want as
select * from connection to odbc
(<code specific to your dbms language>);
disconnect from odbc;
quit;

Export/Import Attributes of a SAS dataset

I am working with multiple waves of survey data. I have finished defining formats and labels for the first wave of data.
The second wave of data will be different, but the codes, labels, formats, and variable names will all be the same. I do not want to define all these attributes again...it seems like there should be a way to export the PROC CONTENTS information for one dataset and import it into another dataset. Is there a way to do this?
The closest thing I've found is PROC CPORT but I am totally confused by it and cannot get it to run.
(Just to be clear I'll ask the question another way as well...)
When you run PROC CONTENTS, SAS tells you what format, labels, etc. it is using for each variable in the dataset.
I have a second dataset with the exact same variable names. I would like to use the variable attributes from the first dataset on the variables in the second dataset. Is there any way to do this?
Thanks!
So you have a MODEL dataset and a HAVE dataset, both with data in them. You want to create WANT dataset which has data from HAVE, with attributes of MODEL (formats, labels, and variable lengths). You can do this like:
data WANT ;
if 0 then set MODEL ;
set HAVE ;
run ;
This works because when the DATA step compiles, SAS builds the Program Data Vector (PDV) which defines variable attributes. Even though the SET MODEL never executes (because 0 is not true), all of the variables in MODEL are created in the PDV when the step compiles.
Importantly, note that if there are corresponding variables with different lengths, the length from MODEL will determine the length of the variable in WANT. So if HAVE has a variable that is longer than the same-named variable in MODEL, it may be truncated. Options VARLENCHK determines whether or not SAS throws a warning/error if this happens.
That assumes there are no formats/labels on the HAVE dataset. If there is a variable in HAVE that has a format/label, and the corresponding variable in MODEL does not have a format/label, the format/label from HAVE will be applied to WANT.
Sample code below.
data model;
set sashelp.class;
length FavoriteColor $3;
FavoriteColor="Red";
dob=today();
label
dob='BirthDate'
;
format
dob mmddyy10.
;
run;
data have;
set sashelp.class;
length FavoriteColor $10;
dob=today()-1;
FavoriteColor="Orange";
label
Name="HaveLabel"
dob="HaveLabel"
;
format
Name $1.
dob comma.
;
run;
options varlenchk=warn;
data want;
if 0 then set model;
set have;
run;
I'd create an empty dataset based on the existing one, and then use proc append to append the contents to it.
Create some sample data for the second round of data:
data new_data;
age = 10;
run;
Create an empty dataset based on the original data:
proc sql noprint;
create table want like sashelp.class;
quit;
Append the data into the empty dataset, retaining the details from the original:
proc append base=want data=new_data force nowarn;
run;
Note that I've used the force and nowarn options on proc append. This will ensure the data is appended even if differences are found between the two datasets being used. This is expected if you have, for example, format differences. It will also hide things like if columns exist in the new table that aren't in the old table etc. So be careful that this is doing what you want it to. If the behaviour is undesirable, consider using a datastep to append instead (and list the want dataset first).
Welcome to the stack.
If you want to copy the properties of the table without the data within it, you could use PROC SQL or data step with zero rows read in.
This examples copies all information about the SASHELP.CLASS dataset into a brand new dataset. All formats, attributes, labels, the whole thing is copies over. If you want to only copy some of the columns, specify them in select clause instead of asterix.
PROC SQL outobs=0;
CREATE TABLE WANT as SELECT * FROM SASHELP.CLASS;
QUIT;
Regards,
Vasilij