Re: Does the speed of a query decrease with the number of indexes? 1. SAS dataset or DBMS table? I am using the SAS Scalable Performance Data Engine. 2. How many rows? Some examples for the files I am accessing. 1,794,533,270 5,080,553,136 1,602,072,953 Largest 10,125,182,001 3. How many fields and bytes per record? largest Data Observations 10125182001 Data Partsize 53477375K There are three parts, so multiply by three That looks like 15 bytes per record. 4. How complex is the query? I use DS2. Create a hash out of my lookup table which has one field: the index field, then load the larger table and output if index value is found. f = h.find();
if (f = 0) then output;
proc ds2;
data cpt_enrolid (overwrite=yes);
dcl double rc f enrolid;
declare char(7) proc1;
declare char(8) cpt;
dcl package hash h(8, '{select distinct proc1 from work.cpt}');
method init();
rc = h.keys([proc1]);
rc = h.data([proc1]);
rc = h.defineDone();
end;
method run();
set {select enrolid, proc1, proctype from DWSC1116.CEMR_O_2012_2016};
f = h.find();
if (f = 0) then output;
end;
enddata;
run;
quit;
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