带更新的 sqlite CTE
sqlite CTE with UPDATE
我希望这不是重复的,我红了一些帖子,但不知道如何解决这个问题。
我有一个table这样的
CREATE TABLE yo (ad INTEGER PRIMARY KEY, pa INTEGER, pd INTEGER);
INSERT INTO yo VALUES
(1,1,1),(2,1,3),(3,1,4),(4,3,5),(5,4,2),(6,3,8),(7,1,9),(8,6,7),(9,3,6);
.header on
.mode column yo
select * from yo;
ad pa pd
---------- ---------- ----------
1 1 1
2 1 3
3 1 4
4 3 5
5 4 2
6 3 8
7 1 9
8 6 7
9 3 6
我可以像这样使用 CTE 创建一个临时 table 来获得 col 'pd' 的深度级别
CREATE table ui AS
WITH RECURSIVE ui(a,l) AS
( VALUES(1,0)
UNION ALL
SELECT yo.ad, ui.l+1
FROM yo JOIN ui ON yo.pa=ui.a
WHERE yo.pa!=yo.ad
ORDER BY 2 desc
)
SELECT a,l FROM ui;
select * from ui;
a l
---------- ----------
1 0
2 1
3 1
4 2
5 3
6 2
8 3
9 2
7 1
然后我想在 table 'yo' 中添加一个列并在其中输入 ui.l
ALTER TABLE yo ADD COLUMN lv INTEGER;
UPDATE yo SET lv=
(SELECT ui.l
FROM ui
WHERE ui.a=yo.ad);
select * from yo;
ad pa pd lv
---------- ---------- ---------- ----------
1 1 1 0
2 1 3 1
3 1 4 1
4 3 5 2
5 4 2 3
6 3 8 2
7 1 9 1
8 6 7 3
9 3 6 2
一切正常。现在我想在 1 个请求中结合临时 table 'ui' 创建和 table 'yo' 更新?
我尝试了很多组合都找不到解决方案,我相信这很明显,但我不够流利。
CTE 创建是否应该像
中那样在更新之前进行
How to use CTE's with update/delete on SQLite?
或者应该将 CTE 计算到 UPDATE
中的 select
提前感谢您的帮助
干杯,
披
这个有效:
WITH RECURSIVE ui(a,l) AS
( VALUES(1,0)
UNION ALL
SELECT yo.ad, ui.l+1
FROM yo JOIN ui ON yo.pa=ui.a
WHERE yo.pa!=yo.ad
ORDER BY 2 desc
)
UPDATE yo SET lv=
(SELECT ui.l
FROM ui
WHERE ui.a=yo.ad);
这也有效:
UPDATE yo SET lv=
(WITH RECURSIVE ui(a,l) AS
( VALUES(1,0)
UNION ALL
SELECT yo.ad, ui.l+1
FROM yo JOIN ui ON yo.pa=ui.a
WHERE yo.pa!=yo.ad
ORDER BY 2 desc
)
SELECT ui.l
FROM ui
WHERE ui.a=yo.ad
);
我希望这不是重复的,我红了一些帖子,但不知道如何解决这个问题。
我有一个table这样的
CREATE TABLE yo (ad INTEGER PRIMARY KEY, pa INTEGER, pd INTEGER);
INSERT INTO yo VALUES
(1,1,1),(2,1,3),(3,1,4),(4,3,5),(5,4,2),(6,3,8),(7,1,9),(8,6,7),(9,3,6);
.header on
.mode column yo
select * from yo;
ad pa pd
---------- ---------- ----------
1 1 1
2 1 3
3 1 4
4 3 5
5 4 2
6 3 8
7 1 9
8 6 7
9 3 6
我可以像这样使用 CTE 创建一个临时 table 来获得 col 'pd' 的深度级别
CREATE table ui AS
WITH RECURSIVE ui(a,l) AS
( VALUES(1,0)
UNION ALL
SELECT yo.ad, ui.l+1
FROM yo JOIN ui ON yo.pa=ui.a
WHERE yo.pa!=yo.ad
ORDER BY 2 desc
)
SELECT a,l FROM ui;
select * from ui;
a l
---------- ----------
1 0
2 1
3 1
4 2
5 3
6 2
8 3
9 2
7 1
然后我想在 table 'yo' 中添加一个列并在其中输入 ui.l
ALTER TABLE yo ADD COLUMN lv INTEGER;
UPDATE yo SET lv=
(SELECT ui.l
FROM ui
WHERE ui.a=yo.ad);
select * from yo;
ad pa pd lv
---------- ---------- ---------- ----------
1 1 1 0
2 1 3 1
3 1 4 1
4 3 5 2
5 4 2 3
6 3 8 2
7 1 9 1
8 6 7 3
9 3 6 2
一切正常。现在我想在 1 个请求中结合临时 table 'ui' 创建和 table 'yo' 更新?
我尝试了很多组合都找不到解决方案,我相信这很明显,但我不够流利。
CTE 创建是否应该像
中那样在更新之前进行How to use CTE's with update/delete on SQLite?
或者应该将 CTE 计算到 UPDATE
中的 select提前感谢您的帮助
干杯, 披
这个有效:
WITH RECURSIVE ui(a,l) AS
( VALUES(1,0)
UNION ALL
SELECT yo.ad, ui.l+1
FROM yo JOIN ui ON yo.pa=ui.a
WHERE yo.pa!=yo.ad
ORDER BY 2 desc
)
UPDATE yo SET lv=
(SELECT ui.l
FROM ui
WHERE ui.a=yo.ad);
这也有效:
UPDATE yo SET lv=
(WITH RECURSIVE ui(a,l) AS
( VALUES(1,0)
UNION ALL
SELECT yo.ad, ui.l+1
FROM yo JOIN ui ON yo.pa=ui.a
WHERE yo.pa!=yo.ad
ORDER BY 2 desc
)
SELECT ui.l
FROM ui
WHERE ui.a=yo.ad
);