[doc] Initial translation of first two section in installation chapter.
/* -*- sql -*-
postgres specific registered procedures,
require the plpgsql language installed
*/
CREATE FUNCTION comma_join (anyarray) RETURNS text AS $$
SELECT array_to_string($1, ', ')
$$ LANGUAGE SQL;;
CREATE AGGREGATE group_concat (
basetype = anyelement,
sfunc = array_append,
stype = anyarray,
finalfunc = comma_join,
initcond = '{}'
);;
CREATE FUNCTION limit_size (fulltext text, format text, maxsize integer) RETURNS text AS $$
DECLARE
plaintext text;
BEGIN
IF char_length(fulltext) < maxsize THEN
RETURN fulltext;
END IF;
IF format = 'text/html' OR format = 'text/xhtml' OR format = 'text/xml' THEN
plaintext := regexp_replace(fulltext, '<[\\w/][^>]+>', '', 'g');
ELSE
plaintext := fulltext;
END IF;
IF char_length(plaintext) < maxsize THEN
RETURN plaintext;
ELSE
RETURN substring(plaintext from 1 for maxsize) || '...';
END IF;
END
$$ LANGUAGE plpgsql;;
CREATE FUNCTION text_limit_size (fulltext text, maxsize integer) RETURNS text AS $$
BEGIN
RETURN limit_size(fulltext, 'text/plain', maxsize);
END
$$ LANGUAGE plpgsql;;