CREATE TABLE t_hierarchy (
id int(10) unsigned NOT NULL AUTO_INCREMENT,
parent int(10) unsigned NOT NULL,
PRIMARY KEY (id),
KEY ix_hierarchy_parent (parent, id)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
DELIMITER $$
CREATE PROCEDURE prc_fill_hierarchy (level INT, fill INT)
BEGIN
DECLARE _level INT;
DECLARE _fill INT;
INSERT
INTO t_hierarchy (id, parent)
VALUES (1, 0);
SET _fill = 0;
WHILE _fill < fill DO
INSERT
INTO t_hierarchy (parent)
VALUES (1);
SET _fill = _fill + 1;
END WHILE;
SET _fill = 1;
SET _level = 0;
WHILE _level < level DO
INSERT
INTO t_hierarchy (parent)
SELECT hn.id
FROM t_hierarchy ho, t_hierarchy hn
WHERE ho.parent = 1
AND hn.id > _fill;
SET _level = _level + 1;
SET _fill = _fill + POWER(fill, _level);
END WHILE;
END
$$
DELIMITER ;
DROP FUNCTION IF EXISTS hierarchy_connect_by_parent_eq_prior_id;
DELIMITER $$
CREATE FUNCTION hierarchy_connect_by_parent_eq_prior_id(value INT) RETURNS INT
NOT DETERMINISTIC
READS SQL DATA
BEGIN
DECLARE _id INT;
DECLARE _parent INT;
DECLARE _next INT;
DECLARE CONTINUE HANDLER FOR NOT FOUND SET @id = NULL;
SET _parent = @id;
SET _id = -1;
IF @id IS NULL THEN
RETURN NULL;
END IF;
LOOP
SELECT MIN(id)
INTO @id
FROM t_hierarchy
WHERE parent = _parent
AND id > _id;
IF @id IS NOT NULL OR _parent = @start_with THEN
SET @level = @level + 1;
RETURN @id;
END IF;
SET @level := @level - 1;
SELECT id, parent
INTO _id, _parent
FROM t_hierarchy
WHERE id = _parent;
END LOOP;
END
$$
DELIMITER ;
START TRANSACTION;
CALL prc_fill_hierarchy(6, 5);
COMMIT;SELECT @r AS _id,
(
SELECT @r := parent
FROM t_hierarchy
WHERE id = _id
) AS parent,
@l := @l + 1 AS lvl
FROM (
SELECT @r := 1218,
@l := 0,
@cl := 0
) vars,
t_hierarchy h
WHERE @r <> 0mysql 책 사서 봐야겠습니다...ㅠㅠ 이거 명확하게 설명해주실 분... ;ㅅ;
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그걸 재귀함수로 만든거겠죠..
데이터 양이 많지 않다면..
그냥 다 불러들여서 PHP에서 하는게 훨씬 효율적일 겁니다.
전 이런구조는 메뉴나 카테고리에 쓰기때문에..
그냥 다 불러서 PHP에서 정렬하는게 훨씬 효율적이더라구요..
어차피 모든 레코드는 다 불러 들여야 할 상황이니..
데이터 양이 많고..
그중에 일부분만 불러내야 한다면 좀 틀리겠네요..