projekt kivitendo

-- @tag: record_links_post_delete_triggers_gl2

-- @description: Datenbankkonsistenz record_links nach Löschen von Dialogbuchungen und Briefen

-- @depends: release_3_5_3

-- When deleting records record_links weren't cleaned up until now

-- This wasn't really a problem apart from the fact that record_links slowly grew

-- but deleting records was seldom enough to not matter

-- Unfortunately delivery_plan decides if an order need to be displayed by the

-- number of record_links, which generates false negatives.

-- so, first clean up the database, and after that create triggers to

-- clean up automatically

DELETE FROM record_links WHERE from_table = 'letter' AND from_id NOT IN (SELECT id FROM letter);

DELETE FROM record_links WHERE to_table   = 'letter' AND to_id   NOT IN (SELECT id FROM letter);

DELETE FROM record_links WHERE from_table = 'gl' AND from_id NOT IN (SELECT id FROM gl);

DELETE FROM record_links WHERE to_table   = 'gl' AND to_id   NOT IN (SELECT id FROM gl);

CREATE OR REPLACE FUNCTION clean_up_record_links_before_letter_delete() RETURNS trigger AS $$

  BEGIN

    DELETE FROM record_links

      WHERE (from_table = 'letter' AND from_id = OLD.id)

         OR (to_table   = 'letter' AND to_id   = OLD.id);

    RETURN OLD;

  END;

$$ LANGUAGE plpgsql;

CREATE OR REPLACE FUNCTION clean_up_record_links_before_gl_delete() RETURNS trigger AS $$

  BEGIN

    DELETE FROM record_links

      WHERE (from_table = 'gl' AND from_id = OLD.id)

         OR (to_table   = 'gl' AND to_id   = OLD.id);

    RETURN OLD;

  END;

$$ LANGUAGE plpgsql;

CREATE TRIGGER before_delete_gl_trigger

BEFORE DELETE ON gl FOR EACH ROW EXECUTE

PROCEDURE clean_up_record_links_before_gl_delete();

CREATE TRIGGER before_delete_letter_trigger

BEFORE DELETE ON letter FOR EACH ROW EXECUTE

PROCEDURE clean_up_record_links_before_letter_delete();