rename sql directory to lib-sql

Also introduces a separate constant for the sql directory, so that it can be put separately from the rest of the data if required.
2021-02-09 15:26:56 +01:00
parent db3ced17bb
commit b9517c99ae
35 changed files with 29 additions and 22 deletions
--- a/lib-sql/functions/importance.sql
+++ b/lib-sql/functions/importance.sql
@@ -0,0 +1,125 @@
+-- Functions for interpreting wkipedia/wikidata tags and computing importance.
+
+DROP TYPE IF EXISTS wikipedia_article_match CASCADE;
+CREATE TYPE wikipedia_article_match as (
+  language TEXT,
+  title TEXT,
+  importance FLOAT
+);
+
+DROP TYPE IF EXISTS place_importance CASCADE;
+CREATE TYPE place_importance as (
+  importance FLOAT,
+  wikipedia TEXT
+);
+
+
+-- See: http://stackoverflow.com/questions/6410088/how-can-i-mimic-the-php-urldecode-function-in-postgresql
+CREATE OR REPLACE FUNCTION decode_url_part(p varchar)
+  RETURNS varchar
+  AS $$
+SELECT convert_from(CAST(E'\\x' || array_to_string(ARRAY(
+    SELECT CASE WHEN length(r.m[1]) = 1 THEN encode(convert_to(r.m[1], 'SQL_ASCII'), 'hex') ELSE substring(r.m[1] from 2 for 2) END
+    FROM regexp_matches($1, '%[0-9a-f][0-9a-f]|.', 'gi') AS r(m)
+), '') AS bytea), 'UTF8');
+$$ 
+LANGUAGE SQL IMMUTABLE STRICT;
+
+
+CREATE OR REPLACE FUNCTION catch_decode_url_part(p varchar)
+  RETURNS varchar
+  AS $$
+DECLARE
+BEGIN
+  RETURN decode_url_part(p);
+EXCEPTION
+  WHEN others THEN return null;
+END;
+$$
+LANGUAGE plpgsql IMMUTABLE STRICT;
+
+
+CREATE OR REPLACE FUNCTION get_wikipedia_match(extratags HSTORE, country_code varchar(2))
+  RETURNS wikipedia_article_match
+  AS $$
+DECLARE
+  langs TEXT[];
+  i INT;
+  wiki_article TEXT;
+  wiki_article_title TEXT;
+  wiki_article_language TEXT;
+  result wikipedia_article_match;
+BEGIN
+  langs := ARRAY['english','country','ar','bg','ca','cs','da','de','en','es','eo','eu','fa','fr','ko','hi','hr','id','it','he','lt','hu','ms','nl','ja','no','pl','pt','kk','ro','ru','sk','sl','sr','fi','sv','tr','uk','vi','vo','war','zh'];
+  i := 1;
+  WHILE langs[i] IS NOT NULL LOOP
+    wiki_article := extratags->(case when langs[i] in ('english','country') THEN 'wikipedia' ELSE 'wikipedia:'||langs[i] END);
+    IF wiki_article is not null THEN
+      wiki_article := regexp_replace(wiki_article,E'^(.*?)([a-z]{2,3}).wikipedia.org/wiki/',E'\\2:');
+      wiki_article := regexp_replace(wiki_article,E'^(.*?)([a-z]{2,3}).wikipedia.org/w/index.php\\?title=',E'\\2:');
+      wiki_article := regexp_replace(wiki_article,E'^(.*?)/([a-z]{2,3})/wiki/',E'\\2:');
+      --wiki_article := regexp_replace(wiki_article,E'^(.*?)([a-z]{2,3})[=:]',E'\\2:');
+      wiki_article := replace(wiki_article,' ','_');
+      IF strpos(wiki_article, ':') IN (3,4) THEN
+        wiki_article_language := lower(trim(split_part(wiki_article, ':', 1)));
+        wiki_article_title := trim(substr(wiki_article, strpos(wiki_article, ':')+1));
+      ELSE
+        wiki_article_title := trim(wiki_article);
+        wiki_article_language := CASE WHEN langs[i] = 'english' THEN 'en' WHEN langs[i] = 'country' THEN get_country_language_code(country_code) ELSE langs[i] END;
+      END IF;
+
+      select wikipedia_article.language,wikipedia_article.title,wikipedia_article.importance
+        from wikipedia_article 
+        where language = wiki_article_language and 
+        (title = wiki_article_title OR title = catch_decode_url_part(wiki_article_title) OR title = replace(catch_decode_url_part(wiki_article_title),E'\\',''))
+      UNION ALL
+      select wikipedia_article.language,wikipedia_article.title,wikipedia_article.importance
+        from wikipedia_redirect join wikipedia_article on (wikipedia_redirect.language = wikipedia_article.language and wikipedia_redirect.to_title = wikipedia_article.title)
+        where wikipedia_redirect.language = wiki_article_language and 
+        (from_title = wiki_article_title OR from_title = catch_decode_url_part(wiki_article_title) OR from_title = replace(catch_decode_url_part(wiki_article_title),E'\\',''))
+      order by importance desc limit 1 INTO result;
+
+      IF result.language is not null THEN
+        return result;
+      END IF;
+    END IF;
+    i := i + 1;
+  END LOOP;
+  RETURN NULL;
+END;
+$$
+LANGUAGE plpgsql STABLE;
+
+
+CREATE OR REPLACE FUNCTION compute_importance(extratags HSTORE,
+                                              country_code varchar(2),
+                                              osm_type varchar(1), osm_id BIGINT)
+  RETURNS place_importance
+  AS $$
+DECLARE
+  match RECORD;
+  result place_importance;
+BEGIN
+  FOR match IN SELECT * FROM get_wikipedia_match(extratags, country_code)
+               WHERE language is not NULL
+  LOOP
+    result.importance := match.importance;
+    result.wikipedia := match.language || ':' || match.title;
+    RETURN result;
+  END LOOP;
+
+  IF extratags ? 'wikidata' THEN
+    FOR match IN SELECT * FROM wikipedia_article
+                  WHERE wd_page_title = extratags->'wikidata'
+                  ORDER BY language = 'en' DESC, langcount DESC LIMIT 1 LOOP
+      result.importance := match.importance;
+      result.wikipedia := match.language || ':' || match.title;
+      RETURN result;
+    END LOOP;
+  END IF;
+
+  RETURN null;
+END;
+$$
+LANGUAGE plpgsql;
+