Hi,
I have the following code to search for neighboring positions
(distance <=10). But it is slow for large data set. I'm wondering what
is the most efficient query for such a search. Note that I don't
create an index, as I'm not sure what index to create on table A.
$ cat main.sql
#!/usr/bin/env bash
rm -f main.db
sqlite3 main.db <<EOF
create table A (name text, position integer);
insert into A values('a', 1);
insert into A values('a', 5);
insert into A values('a', 21);
insert into A values('b', 3);
insert into A values('b', 15);
insert into A values('b', 19);
.mode column
.headers on
.echo on
select * from A as A1, A as A2 where A1.name=A2.name and
abs(A1.position - A2.position) <= 10 and A1.position != A2.position;
EOF
--
Regards,
Peng
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