%let connOptions=DATABASE=test SERVER="verthost" PORT=5433;
%let userpw=user=user-ID password=pw123;
%let sysconnOptions=&userpw. &connOptions.;
%let tabName=zz;

%let engine=sasiovrt;

libname x &engine. &sysconnOptions. ;

%macro execQuery(query);
proc sql;
connect to &engine. (&sysconnOptions. );
execute(&query)by &engine.;
disconnect from &engine.;
quit;
%mend;

%execQuery(DROP TABLE &tabName.);
%execQuery(CREATE TABLE &tabName. ( "name" varchar(4) ));
%execQuery(insert into &tabName.( name) values ( 'test'));
%execQuery(insert into &tabName.( name) values ( ''));
%execQuery(insert into &tabName.( name) values ( ' '));

proc sql; select       *  from x.zz where name = ''; quit;
proc sql; select count(*) from x.zz where name = ''; quit;