hierarchical-data

来源： https://stackoverflow.com/questions/64111630/construct-json-from-data-using-presto

问题 I have two tables; categories and products. For each category i would like to count how many products there are in all of its subcategories. I already have counted how many are in each category. Example tables are: Categories: ID ParentID ProductCount SubCategoryProducts 1 NULL 0 2 1 2 3 2 1 Products: ProductID CategoryID 123 2 124 2 125 3 So i would like my function to make: ID ParentID ProductCount SubCategoryProducts 1 NULL 0 3 2 1 2 1 3 2 1 0 It simply needs to be as a select query, no

问题 I'm trying to make a hierarchical list with PHP and an SQLite table setup like this: | itemid | parentid | name | ----------------------------------------- | 1 | null | Item1 | | 2 | null | Item2 | | 3 | 1 | Item3 | | 4 | 1 | Item4 | | 5 | 2 | Item5 | | 6 | 5 | Item6 | The lists would be built with unordered lists and allow for this type of tree structure: Item1 |_Item3 |_Item4 Item2 |_Item5 |_Item6 I've seen this done with directories and flat arrays, but I can't seem to make it work right

问题 I have two tables in an MS SQL Server 2005 database, parent and child, where the parent may be related to many child records. [Child.parent_id] is related to [parent.id]. The child table also has column [foo] I need to bring back all records in the parent table where [child.foo] matches on each of one to many parameters. For example I would like all parent records that have a [child.foo] value of 'fizz' and a [child.foo] value of 'buzz.' I have tried the below query, but it is returning

问题 ColumnA ColumnB ColumnC ColumnD A B C E D C F E C H I E C W S E1 The logic should be when columnA/columnB has a record in columnC which is columnA/columnB in another record with the same columnD, it will be output as the following ColumnV ColumnW A C B C D F C F C I H I C S W S A F B F A I B I How can I write a sql to get the following: 回答1: I'm not sure if I fully understand the logic you are trying to implement, but here is SQL that creates your table and duplicates your example output. It

问题 ColumnA ColumnB ColumnC ColumnD A B C E D C F E C H I E C W S E1 The logic should be when columnA/columnB has a record in columnC which is columnA/columnB in another record with the same columnD, it will be output as the following ColumnV ColumnW A C B C D F C F C I H I C S W S A F B F A I B I How can I write a sql to get the following: 回答1: I'm not sure if I fully understand the logic you are trying to implement, but here is SQL that creates your table and duplicates your example output. It

问题 I want to build a hierarchical data structure from my sql query. After following this post for build hierarchical JSON object from flat objects, I try to create 4 level hierarchy with more attributes in object levels, but don't need children property. How can i do this? Here is my JavaScript (NodeJS) code: var levels = ["counties_id","district_id", "municipalities_id", "institutes_id"]; data.forEach(function(d){ var depthCursor = newData.counties; levels.forEach(function( property, depth ){

问题 In MySQL, I store categories this way: categories: - category_id - category_name - parent_category_id What would be the most efficient way to generate the trail / breadcrumb for a given category_id? For example breadcrumbs(category_id): General > Sub 1 > Sub 2 There could be in theories unlimited levels. I'm using php. UPDATE: I saw this article (http://mikehillyer.com/articles/managing-hierarchical-data-in-mysql/) about the Nested Set Model. It looks interesting, but how would you ago about

问题 In MySQL, I store categories this way: categories: - category_id - category_name - parent_category_id What would be the most efficient way to generate the trail / breadcrumb for a given category_id? For example breadcrumbs(category_id): General > Sub 1 > Sub 2 There could be in theories unlimited levels. I'm using php. UPDATE: I saw this article (http://mikehillyer.com/articles/managing-hierarchical-data-in-mysql/) about the Nested Set Model. It looks interesting, but how would you ago about

问题 In MySQL, I store categories this way: categories: - category_id - category_name - parent_category_id What would be the most efficient way to generate the trail / breadcrumb for a given category_id? For example breadcrumbs(category_id): General > Sub 1 > Sub 2 There could be in theories unlimited levels. I'm using php. UPDATE: I saw this article (http://mikehillyer.com/articles/managing-hierarchical-data-in-mysql/) about the Nested Set Model. It looks interesting, but how would you ago about