--- /dev/null
+DELIMITER $
+CREATE FUNCTION
+ m_remove_bracketed_text(str TEXT)
+ RETURNS TEXT
+ DETERMINISTIC
+ BEGIN
+ RETURN REPLACE(str, SUBSTRING(str, LOCATE('(', str), LENGTH(str) - LOCATE(')', REVERSE(str)) - LOCATE('(', str) + 2), '');
+ END
+$
+DELIMITER ;
+
+DROP FUNCTION IF EXISTS m_split_string;
+DELIMITER $
+CREATE FUNCTION
+ m_split_string (s TEXT, del VARCHAR(10), i INT)
+ RETURNS TEXT
+ DETERMINISTIC
+ BEGIN
+ DECLARE n INT ;
+ SET n = LENGTH(s) - LENGTH(REPLACE(s, del, '')) + 1;
+ IF i > n THEN
+ RETURN NULL ;
+ ELSE
+ RETURN SUBSTRING_INDEX(SUBSTRING_INDEX(s, del, i) , del , -1 ) ;
+ END IF;
+ END
+$
+DELIMITER ;
+
+DROP FUNCTION IF EXISTS m_string_segment_count;
+DELIMITER $
+CREATE FUNCTION
+ m_string_segment_count(s TEXT, del VARCHAR(10))
+ RETURNS TEXT
+ DETERMINISTIC
+ BEGIN
+ DECLARE n INT ;
+ SET n = LENGTH(s) - LENGTH(REPLACE(s, del, '')) + 1;
+ RETURN n;
+ END
+$
+DELIMITER ;
+
--- /dev/null
+
+-- pass it the biblionumber, the position of the character to start in the leader starting at 0
+-- and the text to replace, single characer or multiple
+DROP FUNCTION IF EXISTS m_update_leader;
+DELIMITER $
+CREATE FUNCTION
+ m_update_leader(bnumber INTEGER, ldr_position SMALLINT, new_value TEXT)
+ RETURNS BOOLEAN
+ DETERMINISTIC
+ BEGIN
+ DECLARE ldr TEXT COLLATE utf8mb4_unicode_ci DEFAULT NULL;
+ DECLARE new_value_length SMALLINT DEFAULT 1;
+ SET ldr_position = ldr_position + 1;
+ SET new_value_length = LENGTH(new_value);
+
+ SELECT ExtractValue(metadata, '//leader') INTO ldr FROM biblio_metadata WHERE biblionumber = bnumber;
+ SET ldr = INSERT(ldr,ldr_position,new_value_length,new_value);
+ SET ldr = CONCAT('<leader>',ldr,'</leader>');
+
+ UPDATE biblio_metadata SET metadata = UpdateXML(metadata, '//leader', ldr) where biblionumber = bnumber;
+ RETURN TRUE;
+
+ END
+$
+DELIMITER ;
+
+