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2
votes
1answer
6k views

Recursive Query in MySQL using stored proceedure and CURSOR

I'm expanding our user/group system to allow for dynamic groups which are made up of other groups members. I have three tables users, groups, and relationships. For simplicity sake, lets say users ...
15
votes
3answers
4k views

Traversing tree-like data in a relational database using SQL

Is there a way to traverse tree data in SQL? I know about 'connect by' in Oracle, but is there another way to do this in other SQL implementations? I'm asking because using 'connect by' is easier ...
3
votes
2answers
835 views

Best design for a tree-like structure database

I'm designing a database in MS Access which is used for tracking the locations of a variety of chemical solutions, made in batches. Each batch can be split (aliquoted) practically indefinitely. That ...
1
vote
1answer
248 views

Implement a Parent-Level Count in Binary Search Tree

Based on this question, have any way to implement a parent level count? Find highest level of a hierarchical field: with vs without CTEs Example table: +----+-----------+ | id | parent_id | ...
4
votes
2answers
6k views

COUNT of rows with parent id equal to the row we have with a parent id of 0 in one query

I'd like to do the following in one query using MySQL: grab a row that has a parent_id of 0 grab a count of all the rows that have a parent_id of the row that we grabbed which has a parent_id of 0 ...