X-Git-Url: https://git.openstreetmap.org./rails.git/blobdiff_plain/ff7ddb6b86bf918a9418af7382836b41594d45e4..8cef62cd2cec4a297e46b4f2a86c9afeadb3b283:/db/functions/functions.sql diff --git a/db/functions/functions.sql b/db/functions/functions.sql index 4f1f7c716..97e44f0ce 100644 --- a/db/functions/functions.sql +++ b/db/functions/functions.sql @@ -40,61 +40,3 @@ BEGIN RETURN (x << 1) | y; END; $$ LANGUAGE plpgsql IMMUTABLE; - - --- maptile_for_point returns an integer representing the tile at the given zoom --- which contains the point (scaled_lon, scaled_lat). Note that the arguments --- are in the order (lat, lon), and should be scaled by 10^7. --- --- The maptile_for_point function is used only for grouping the results of the --- (deprecated?) /changes API call. Please don't use it for anything else, as --- it might go away in the future. -CREATE OR REPLACE FUNCTION maptile_for_point(scaled_lat int8, scaled_lon int8, zoom int4) - RETURNS int4 - AS $$ -DECLARE - lat CONSTANT DOUBLE PRECISION := scaled_lat / 10000000.0; - lon CONSTANT DOUBLE PRECISION := scaled_lon / 10000000.0; - zscale CONSTANT DOUBLE PRECISION := 2.0 ^ zoom; - pi CONSTANT DOUBLE PRECISION := 3.141592653589793; - r_per_d CONSTANT DOUBLE PRECISION := pi / 180.0; - x int4; - y int4; -BEGIN - -- straight port of the C code. see db/functions/maptile.c - x := floor((lon + 180.0) * zscale / 360.0); - y := floor((1.0 - ln(tan(lat * r_per_d) + 1.0 / cos(lat * r_per_d)) / pi) * zscale / 2.0); - - RETURN (x << zoom) | y; -END; -$$ LANGUAGE plpgsql IMMUTABLE; - --- xid_to_int4 converts a PostgreSQL transaction ID (xid) to a 32-bit integer --- which can then be used to efficiently find rows which have changed between --- two given transactions. This is currently used by Osmosis to extract a --- stream of edits for "diff replication" **HOWEVER** this is a pain point, as --- (ab)using the xid in this way is _not_ supported or recommended by Postgres --- devs. It is preventing us upgrading to PostgreSQL version 10+, and will --- hopefully be replaced Real Soon Now. --- --- From the Osmosis distribution by Brett Henderson: --- https://github.com/openstreetmap/osmosis/blob/master/package/script/contrib/apidb_0.6_osmosis_xid_indexing.sql -CREATE OR REPLACE FUNCTION xid_to_int4(t xid) - RETURNS integer - AS -$$ -DECLARE - tl bigint; - ti int; -BEGIN - tl := t; - - IF tl >= 2147483648 THEN - tl := tl - 4294967296; - END IF; - - ti := tl; - - RETURN ti; -END; -$$ LANGUAGE 'plpgsql' IMMUTABLE STRICT;