family tree database

"TV580" parent node, parent_id is-1 Call Pro_show_parentlst (); Mysql> call Pro_show_parentlst; | ID | NAME | parent_id | Depth | Path | pathname | | 14 | --tv580 | -1 | 0 | -1/14 | tv580/| 1 row in Set (0.02 sec) Query OK, 0 rows affected (0.02 sec) 3.9, displaying the parent node of the Help node Call Pro_show_parentlst (); Mysql> call Pro_show_parentlst; | ID | NAME | parent_id | Depth | Path | pathname | | 17 | --Help | 14 | 0 | -1/14/17 | tv580/Help/| | 14 | --tv580 |

operation can only be recursive operation less than 32 layer, otherwise will be error, and this recursive call performance is not good. But you can learn the use of triggersALTER TRIGGER [dbo].[Myfirsttrigger] on [dbo].[sharetable] for DELETE as BEGIN --SET NOCOUNT on; DECLARE @id INT,--share ID; @customer VARCHAR( $), @tocustomer VARCHAR( $), @taskId VARCHAR( -) --SELECT @id=Id@customer=Customer@tocustomer=Tocustomer fromDELETED; DELETE fromDbo. Sha

Tags: Select enumeration sel field share picture technology There's a GES ikeToday, we introduce the second method of storing tree structure into database--Path enumeration method. Or borrow the last one of the chestnuts, in order to facilitate the inspection, I took the picture and moved over. There are still a few questions to answer: 1. Check with your immediate boss for a small day. 2. Query the immedi

Tags: Body problem info alt Question Tool EXT TPS CascadeQuestion: Two level linkage, multi-level linkage and other tree structure data, how to design the table.Scene: Three-level linkage of provincial and municipal counties, classification of commodities.Reference: https://www.zhihu.com/question/20417447One of the most commonly used methods is to put multilevel data in the same table, each of which hires a parent_id field to hold the ID of its corres

Include "config.php";Include "mysql.php";$db = new Mysql (' Test '); There are a few simple classes that you can read without being listed. is to instantiate a database connection.function Rootmenu ($PID, $n) {Global $arr, $db;$sql = "Select * from menu where ' PID ' = $PID";$result = $db->query ($sql);while ($i = $db->fetch_array ($result)) {$i ["title"] =str_repeat ('--', $n). $i ["title"];$arr [] = $i;Rootmenu ($i ["ID"], ($n +4));}return $arr;}$ar

Array ([0] = = Array ([id] = 1 [PID] + 0 [name] = Shandong [Children] = = Array ([0] = = Array ( [id] = 3 [PID] + 1 [name] = Jinan [Children] = = Array ([0] = = Array ([id] = 7 [PID] = 3 [name] = Lixia District [children] = = Array (