There are some other factors that create differences between Fact Table and Dimension Table to view them, let’s have a glance at the comparison chart show below. This is because this data is meant to be consumed by front-end web apps and supplying the actual data as opposed to the database record ids reducesthe amount of queries the front-end has to make of the back-end in order to retrieve the data it needs.Īgain - the goal of this job is to create a recursive (PostgreSQL) SQL query which generates JSON matching that found in the attached results.json file.The point that distinguishes Fact table and Dimension table is that the dimension table contains attributes along which measures are taken in fact table. Unlike the data stored in the database - child ids are replaced by the actual child data. You will see all the ```child``` data associated with each respective ```parent```. "review": "Couldn't sleep for a week - amazing writing !!!" 'is_association' - a boolean indicating whether or not the current attribute describes a relationship between the current ('parent') object and a child (or set of child objects)Īn Author can have one or more Book's. 'accessor' - describes the name of the accessor that can be used to access the value associated with this attribute from its 'parent' object 'label' - describes the label to use in a future user interface An attribute of type 'array' is designed to contain an array of ```ids``` of 'child' records (an example of a ```parent -> child``` relationship will be provided below)
![create a unique index postico create a unique index postico](https://live.staticflickr.com/8001/6981966070_14d4b95cda_b.jpg)
this 'type' is the only one that needs additional explanation.
![create a unique index postico create a unique index postico](https://i.pinimg.com/originals/d7/f5/4b/d7f54ba838eb1bd30f33a630e1027ddb.jpg)
'type' - describes the data type of the attribute. Īttributes in any data model described in the ```resources``` table are defined using the same set of 'keys'. Here's the JSON definition of an ```Author```. The data model contained within the attached 'seed_data.sql' defines an ```Author``` object. The one I've defined in the supplied sample is relatively simple - but complex enough to make it interesting.
#Create a unique index postico free#
Because the schema attribute is JSON - users are free to define an arbitrarily complex data model. That definition is stored in the schema attribute. The primary purpose of the resources table is store a definition of the models used by the system.
![create a unique index postico create a unique index postico](https://www.mssqltips.com/tipimages2/4270_index_creation.jpg)
![create a unique index postico create a unique index postico](https://spin.atomicobject.com/wp-content/uploads/20190311180154/postico.png)
Understanding the data model of the two tables ( resources and resource_data) is essential to performing this task. populate the database with the supplied 'seed' data.I'm going to assume that you know how to. Indices -ĬREATE UNIQUE INDEX resources_pkey ON resources(id int8_ops) ĬREATE UNIQUE INDEX resource_data_pkey ON resource_data(id int8_ops) Ī file containing insert statements necessary to populate these two tables can be found in the attached file 'seed_data.sql'. Updated_at timestamp(6) without time zone NOT NULL Table Definition -Ĭreated_at timestamp(6) without time zone NOT NULL, Not all database features are supported.