All,
Here are the query plans for two queries, identical except for the name
of the intersection function:
First, with Intersects():
explain
select Buffer(nodepoint, :wh_radius, 4) as wh_geometry
from byway_extension be, byway_current b
where
be.byway_id != b.id
and Intersects(be.extension, b.geometry);
QUERY PLAN
-------------------------------------------------------------------------------------
Nested Loop (cost=684.78..97841763.45 rows=1262371587 width=32)
Join Filter: ((be.byway_id <> bs.id) AND intersects(be.extension,
bs.geometry))
-> Seq Scan on byway_segment bs (cost=0.00..6578.20 rows=151607 width=100)
Filter: ((NOT deleted) AND (valid_before_rid = 2000000000))
-> Materialize (cost=684.78..934.58 rows=24980 width=68)
-> Seq Scan on byway_extension be (cost=0.00..659.80 rows=24980
width=68)
Second, with ST_Intersects():
explain
select Buffer(nodepoint, :wh_radius, 4) as wh_geometry
from byway_extension be, byway_current b
where
be.byway_id != b.id
and ST_Intersects(be.extension, b.geometry);
QUERY PLAN
-------------------------------------------------------------------------------------------------------------
Nested Loop (cost=0.00..31033.43 rows=6312 width=32)
Join Filter: ((be.byway_id <> bs.id) AND _st_intersects(be.extension,
bs.geometry))
-> Seq Scan on byway_extension be (cost=0.00..659.80 rows=24980 width=68)
-> Index Scan using byway_segment_gist on byway_segment bs
(cost=0.00..1.20 rows=1 width=100)
Index Cond: (be.extension && bs.geometry)
Filter: ((NOT bs.deleted) AND (bs.valid_before_rid = 2000000000) AND
(be.extension && bs.geometry))
Note the wildly different plans; the first uses no indexes. I was under
the impression that while the old names were deprecated, the
functionality was identical to the new names. No?
Thanks,
Reid
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