How does exact match work?
Well, it's quite stupid because swish-e doesn't allow you to make exact
match to words. So, work-around is to add 'xxbxx' word at beginning of
string and 'xxexx' word at end (think of it as xxb(egin)xx and xxe(nd)xxx)
and then search for phrase (words in particular order).
So, title "human" will be indexed as "xxbxx human xxexx" if you want full
exact match. Then you can search it using (numbers are parameters to e[nr]
field in html forms):
1: exact match from beginning "xxbxx human"
2: exact match from end "human xxexx" (not really useful)
3: exact match begin and end "xxbxx human xxexx"
add 4 to those values (numbers are really bit-masks :-) to produce wild-card
match:
5: exact from beginning with wild-card "xxbxx human*"
6: exact from end with wild-card "human* xxexx"
7: exact begin+end with wild-card "xxbxx human* xxexx"
So, to define field which have to be searched using exact match with wild-card
on TitleAndResponsibility, you would use:
What are bit-masks?
Bit-mask is usage of one byte (8 bits) as 8 separate bits with it's own
meaning (this is simplification, but bear with me for now).
So, 1 = 2^0, thus it's bit 1. With analogy, 2=2^1 and 3=2^0+2^1.
So, for 1-3 we use two bits and have:
number bits
1 01 (just begin bit set)
2 10 (just end bit set)
3 11 (begin and end bit set)
Thus, with two bits (and values 1-3) we can express should we exact match from
beginning, end or both. For wild-card match, we use additional bit 3 (2^3 = 4)
so we have:
number bits exact match
1 001 begin
2 010 end
3 011 begin+end
4 100 (not used)
5 101 (4+1) begin+wild-card
6 110 (4+2) end+wild-card
7 111 (4+3) begin+end+wild-card