What is the easiest way to simulate an SQL "IN" statement - openedge

Question

What is the easiest way to achieve the "IN" SQL functionality in Progress? Here is my code block, and I want to limit this query to 5 different pin numbers for my test. I'd rather not use a string of "OR"s if I can avoid that.
//using the "IN" way with specific pin numbers
FOR EACH names NO-LOCK WHERE names.m-date GE 1/1/1900: //AND names.pin IN (179,198,200,201,210)
FOR EACH nacminfo NO-LOCK WHERE nacminfo.pin = names.pin:
FIND FIRST nacmtype WHERE nacmtype.contact_type_num EQ nacminfo.contact_type_num
AND nacmtype.descr MATCHES ("~*" + "email") NO-LOCK NO-ERROR.
IF AVAILABLE nacmtype THEN DO:
DISPLAY
nacmtype.type_val
nacmtype.descr.
END.
END.
END.

Answer 1

As Stefan says, you can use LOOKUP but performance may suffer since you will need to compare every record with the list.
Using a series of OR comparisons can be very efficient and if the list is short and static (like your example) not at all hard to do.
If the list is longer or changes frequently or if it is held in a variable then you might consider iterating over the list outside the FOR EACH.
Something like this:
define variable i as integer no-undo.
define variable j as integer no-undo.
define variable n as integer no-undo.
define variable myList as character no-undo.
myList = "179,198,200,201,210".
n = num-entries( myList ).
do j = 1 to n:
FOR EACH names NO-LOCK WHERE names.m-date GE 1/1/1900 AND names.pin = entry( j, myList ):
FOR EACH nacminfo NO-LOCK WHERE nacminfo.pin = names.pin:
FIND FIRST nacmtype NO-LOCK
WHERE nacmtype.contact_type_num EQ nacminfo.contact_type_num
AND nacmtype.descr MATCHES ("~*" + "email") NO-ERROR.
IF AVAILABLE nacmtype THEN DO:
DISPLAY
nacmtype.type_val
nacmtype.descr.
END.
END.
END.
end.
Or, finally, transform the list into a temp-table. Something like this:
define temp-table tt_myList no-undo
  field namePIN as character
  index namePIN-idx is unique primary namePIN.
.
define variable i as integer no-undo.
define variable n as integer no-undo.
define variable myList as character no-undo.
myList = "179,198,200,201,210".
/* build a TT */
n = num-entries( myList ).
do i = 1 to n:
  create tt_myList.
  tt_myList.namePIN = entry( i, myList ).
end.
for each tt_myList:
FOR EACH names NO-LOCK WHERE names.m-date GE 1/1/1900 AND names.pin = tt_myList.repName:
FOR EACH nacminfo NO-LOCK WHERE nacminfo.pin = names.pin:
FIND FIRST nacmtype NO-LOCK
WHERE nacmtype.contact_type_num EQ nacminfo.contact_type_num
AND nacmtype.descr MATCHES ("~*" + "email") NO-ERROR.
IF AVAILABLE nacmtype THEN DO:
DISPLAY
nacmtype.type_val
nacmtype.descr.
END.
END.
END.
end.
You could join the TT in the FOR EACH but it won't really make any difference and, personally, I find the nested FOR EACH syntax more natural.
Do you really need that FIRST? Can there ever be more than one record in the result of that FIND?
Lastly, MATCHES isn't doing you any performance favors. Hopefully the other parts of the WHERE clause are narrowing the result set enough that its impact is minimal.

Answer 2

Beware of the performance, since a function on the left side generally cannot use an index, but you can use the lookup function:
for each names
where names.m-date ge 1/1/1990
and lookup( string( names.pin ), '179,198,200,201,210' ) ) > 0
no-lock:
// do something
end.

Answer 3

I'd rather not use a string of "OR"s if I can avoid that.
As Stefan notes, using a function in the WHERE clause means that you will not use any indexes. That will impact performance, possibly very badly.
Look into using dynamic queries to build a WHERE clause with a a bunch of OR names.pin = 179 phrases.
You will need to tweak the building of the where string to make sure that it uses the best indexes available (and that's a huge topic by itself). You can see what indexes are used via the LOG-MANAGER - see https://docs.progress.com/bundle/openedge-abl-troubleshoot-applications-122/page/Query-information-logged.html for some info on this.
define variable pins as integet extent 5 initial [179,198,200,201,210] no-undo.
define variable loop as integer no-undo.
define variable cnt as integer no-undo.
define variable whereString as character no-undo.
define query q1 for names.
whereString = ' for each names no-lock where names.m-date GE 1/1/1900'.
cnt = extent(pins).
do loop = 1 to cnt:
whereSTring = whereSTring + substitute(' OR names.pin = &1', pins[loop]).
end.
query q1:query-prepare(whereString).
query q1:query-open().
query q1:get-first().
do while available names:
// do something with the names
query q1:get-next().
end.
finally:
query q1:query-close().
end finally.