Say we have this tables t1 -------------------------------- category_id | name | lft | rgt --------------------------------
http://dev.mysql.com/tech-resources/articles/hierarchical-data.html LOCK TABLE nested_category WRITE; SELECT @myLeft := lft FROM nested_category
In the query below there is a field called main which is used to differentiate the categorie开发者_如何学Cs.
I am having a problem with awesome_nested_set duplicating children in a select (as the title says) I have the following data in the table (phpmyadmin put quotes around the fields):
when i search on the internet about nest开发者_如何学Pythoned set, everyone assume i have already left and right values. but i dont have (; i have id, name, parent_id as column. how can i find left an
I have to manage some hierarchical data for my web application. The data consist of messages of four types. I decided to use nested-list model because there can be arbitrary number of child nodes in t
This is illegal in Matlab a = [[1];[2 3]] In languages that allow this, this is called nested arrays. I found a way of doing the same in Matlab:
I want to store a tree structure of arbitrary depth in an SQL database (MySQL, but want to avoid DBMS-specific features). Now I want to compute a value N for each node as follows:
I have an MPTT tree of over 100,000 records stored in MySQL using lft, rght and parent_id columns. Now the left/right values became corrupted, while the parent ids are still intact. 开发者_Python百科I
I currently have a query that contains a self-join to query all the direct and indirect managers of an employee from a table that stores company organization info using the nested sets model.In this S
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