libname myimp impala dsn=dsn-name database=database-name user=user-ID
password=password;

NOTE: Libref MYIMP was successfully assigned as follows:
      Engine:        IMPALA
      Physical Name: impala_prod

proc means data=myimp.sas_class;
var weight;
run;

ERROR: Error during in-database processing.
ERROR: ERROR: [unixODBC][Cloudera][DSI] (20032) Required setting 'UID' is not
       present in the connection settings.

libname myimp impala database=database-name  host=host-name  port=21050 UID="user-id"
PWD="password"
conopts='Driver={Impala};AuthMech=3;UseSASL=1;SSL=1;TrustedCerts=your.pem; StringColumnLength=2000';