The module provides new operators.

| Operator | Returns | Description

| ------------------- | ------- | ----------------------------------------------

| tsvector>< tsquery | float4 | Returns distance between tsvector and tsquery.

| Operator| Returns | Description

| -------------------- | ------- | ----------------------------------------------

| tsvector<-> tsquery | float4 | Returns distance between tsvector and tsquery.

And we can execute the following queries:

FROM test_rum

WHERE a @@ to_tsquery('english','beautiful | place')

ORDER BY a<-> to_tsquery('english','beautiful | place');

t | rank

The situation is most beautiful |0.0303964

It is a beautiful |0.0303964

It lookslike a beautiful place |0.0607927

(3 rows)

FROM test_rum

WHERE a @@ to_tsquery('english','place | situation')

ORDER BY a<-> to_tsquery('english','place | situation');

t | rank

The situation is most beautiful |0.0303964

457 | Fri May 20 20:21:22.326724 2016 | 367197.326724

(5 rows)

--to be fixed

--EXPLAIN (costs off)

--SELECT id, d, d <-> '2016-05-16 14:21:25' FROM tsts ORDER BY d <-> '2016-05-16 14:21:25' LIMIT 5;

--SELECT id, d, d <-> '2016-05-16 14:21:25' FROM tsts ORDER BY d <-> '2016-05-16 14:21:25' LIMIT 5;

EXPLAIN (costs off)

SELECT id, d, d <-> '2016-05-16 14:21:25' FROM tsts ORDER BY d <-> '2016-05-16 14:21:25' LIMIT 5;

QUERY PLAN

-----------------------------------------------------------------------------------

Limit

-> Index Scan using tsts_idx on tsts

Order By: (d <-> 'Mon May 16 14:21:25 2016'::timestamp without time zone)

(3 rows)

SELECT id, d, d <-> '2016-05-16 14:21:25' FROM tsts ORDER BY d <-> '2016-05-16 14:21:25' LIMIT 5;

id | d | ?column?

-----+---------------------------------+-------------

355 | Mon May 16 14:21:22.326724 2016 | 2.673276

356 | Mon May 16 15:21:22.326724 2016 | 3597.326724

354 | Mon May 16 13:21:22.326724 2016 | 3602.673276

357 | Mon May 16 16:21:22.326724 2016 | 7197.326724

353 | Mon May 16 12:21:22.326724 2016 | 7202.673276

(5 rows)

ORDER BY a <-> to_tsquery('pg_catalog.english', 'way');

rum_ts_distance | t | a

-----------------+--------------------------------------------------------------------------+---------------------------------------------------------------

0.0607927 | my appreciation of you in a more complimentary way than by sending this | 'appreci':2 'complimentari':8 'send':12 'way':9

0.0607927 | itself. Put on your “specs” and look at the castle, half way up the | 'castl':10 'half':11 'look':7 'put':2 'spec':5 'way':12

0.0607927 | so well that only a fragment, as it were, gave way. It still hangs as if | 'fragment':6 'gave':10 'hang':14 'still':13 'way':11 'well':2

0.0607927 | thinking--“to go or not to go?” We are this far on the way. Reached | 'far':11 'go':3,7 'reach':15 'think':1 'way':14

16.4493 | my appreciation of you in a more complimentary way than by sending this | 'appreci':2 'complimentari':8 'send':12 'way':9

16.4493 | itself. Put on your “specs” and look at the castle, half way up the | 'castl':10 'half':11 'look':7 'put':2 'spec':5 'way':12

16.4493 | so well that only a fragment, as it were, gave way. It still hangs as if | 'fragment':6 'gave':10 'hang':14 'still':13 'way':11 'well':2

16.4493 | thinking--“to go or not to go?” We are this far on the way. Reached | 'far':11 'go':3,7 'reach':15 'think':1 'way':14

(4 rows)

SELECT rum_ts_distance(a, to_tsquery('pg_catalog.english', 'way & (go | half)')), *

ORDER BY a <-> to_tsquery('pg_catalog.english', 'way & (go | half)');

rum_ts_distance | t | a

-----------------+---------------------------------------------------------------------+---------------------------------------------------------

0.103556 | thinking--“to go or not to go?” We are this far on the way. Reached | 'far':11 'go':3,7 'reach':15 'think':1 'way':14

0.0991032 | itself. Put on your “specs” and look at the castle, half way up the | 'castl':10 'half':11 'look':7 'put':2 'spec':5 'way':12

9.65659 | thinking--“to go or not to go?” We are this far on the way. Reached | 'far':11 'go':3,7 'reach':15 'think':1 'way':14

10.0905 | itself. Put on your “specs” and look at the castle, half way up the | 'castl':10 'half':11 'look':7 'put':2 'spec':5 'way':12

(2 rows)

SELECT

a <-> to_tsquery('pg_catalog.english', 'way & (go | half)'),

rum_ts_distance(a, to_tsquery('pg_catalog.english', 'way & (go | half)')),

*

FROM test_rum

ORDER BY a <-> to_tsquery('pg_catalog.english', 'way & (go | half)') limit 3;

?column? | rum_ts_distance | t | a

----------+-----------------+-------------------------------------------------------------------------+---------------------------------------------------------

9.65659 | 9.65659 | thinking--“to go or not to go?” We are this far on the way. Reached | 'far':11 'go':3,7 'reach':15 'think':1 'way':14

10.0905 | 10.0905 | itself. Put on your “specs” and look at the castle, half way up the | 'castl':10 'half':11 'look':7 'put':2 'spec':5 'way':12

1e+20 | 1e+20 | my appreciation of you in a more complimentary way than by sending this | 'appreci':2 'complimentari':8 'send':12 'way':9

(3 rows)

INSERT INTO test_rum (t) VALUES ('foo bar foo the over foo qq bar');

INSERT INTO test_rum (t) VALUES ('345 qwerty copyright');

INSERT INTO test_rum (t) VALUES ('345 qwerty');

'bar':2,8 'foo':1,3,6 'qq':7

(1 row)

DELETE FROM test_rum;

SELECT count(*) from test_rum;

count

-------

0

(1 row)

CREATE TABLE tst (i int4, t tsvector);

INSERT INTO tst SELECT i%10, to_tsvector('simple', substr(md5(i::text), 1, 1)) FROM generate_series(1,100000) i;

CREATE INDEX tstidx ON tst USING rum (t rum_tsvector_ops);