Hierarchical data<\/h2>\n<\/div>\n<\/div>\n

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• Hierarchical data is a common relational data pattern for representing tree-like data structures, such as an organizational structure, a project breakdown list, or even a family tree.<\/li>\n<\/ul>\n<\/div>\n<\/div>\n
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  • In relational database model, One thing to remember is that flexibility in keys.<\/li>\n
  • We have the flexibility to design the database, it might be worth having multiple geometry types for certain data types.<\/li>\n
  • For example, having a city represented as a polygon would be useful to perform spatial queries to determine all points of interest within that city.<\/li>\n
  • At the same time, it is oftentimes more desirable to represent a city as a point on a map. The database allows you to do this by separating the attribute data from the features into their own table, and linking them together with a Primary Key\/Foreign Key structure.<\/li>\n<\/ul>\n<\/div>\n<\/div>\n
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    Primary Key:<\/h2>\n<\/div>\n<\/div>\n

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    • A Primary Key is an identifier for a record in a table.<\/li>\n<\/ul>\n<\/div>\n<\/div>\n
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      Foreign Key:<\/h2>\n<\/div>\n<\/div>\n

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      • A Foreign Key is a reference to that same identifier in a different table, thus linking them together.<\/li>\n<\/ul>\n<\/div>\n<\/div>\n
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        CREATE DATABASE testDB:<\/h2>\n<\/div>\n<\/div>\n

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        • We want to includes this tables to the database:<\/li>\n
        • Continent – Fields – Geom (Polygon), ID(Primary Key), Name, Etc<\/li>\n<\/ul>\n<\/div>\n<\/div>\n
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          CREATE TABLE<\/span> Continent (\r\n    ID int NOT NULL PRIMARY KEY,\r\n    Name varchar<\/span>(255) NOT NULL,\r\n    Geom_Polygon varchar<\/span>(255),\r\n    Age int\r\n);\r\n<\/strong><\/span><\/code><\/pre>\n<\/figure>\n<\/div>\n<\/div>\n
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          Country – Fields – Geom (Polygon), ID, Name, Continent ID(Foreign Key)<\/p>\n<\/div>\n<\/div>\n
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          CREATE TABLE<\/span> Country (\r\n    ID int NOT NULL PRIMARY KEY,\r\n    Name varchar<\/span>(255) NOT NULL,\r\n    Geom_Polygon varchar<\/span>(255),\r\n    Continent_id int FOREIGN KEY REFERENCES Continent (ID)\r\n);<\/strong><\/span><\/code><\/pre>\n<\/figure>\n<\/div>\n<\/div>\n
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          Region:<\/h2>\n<\/div>\n<\/div>\n
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          If there are different levels of regions within a country, then we would have them as different layers.<\/li>\n
          So, if a country has regions called districts, and a number of districts combine to form a state, which then combine to form the country, you would have a layer for each type.<\/li>\n
          Reg_State – Fields – Geom (Polygon), ID (Primary Key), Name, Country ID, Etc<\/li>\n<\/ul>\n<\/div>\n<\/div>\n
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          CREATE TABLE<\/span> Reg_State (\r\n    ID int NOT NULL PRIMARY KEY,\r\n    Name varchar<\/span>(255) NOT NULL,\r\n    Geom_Polygon varchar<\/span>(255),\r\n    Country_id int FOREIGN KEY REFERENCES Country<\/span>(ID)\r\n);<\/strong><\/span><\/code><\/pre>\n<\/figure>\n<\/div>\n<\/div>\n
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          Cities:<\/h2>\n<\/div>\n<\/div>\n
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          Have a table that contains attributes for each city, but no geometry.<\/li>\n
          Have geometry tables with different geometries, like point or polygon, that link to the main city table.<\/li>\n
          City_Info – Fields – CityID (Primary key), Name,Reg_District ID (Foreign Key), Etc,<\/li>\n<\/ul>\n<\/div>\n<\/div>\n
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          CREATE TABLE<\/span> City_Info (\r\n    CityID int NOT NULL PRIMARY KEY,\r\n    Name varchar<\/span>(255) NOT NULL,\r\n    Reg_District_id int FOREIGN KEY REFERENCES District<\/span>(ID)\r\n);<\/span><\/code><\/strong><\/pre>\n<\/figure>\n<\/div>\n<\/div>\n
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          City_Pt – Fields – Geom (Point), ID, Name, CityID (Foreign Key)<\/p>\n<\/div>\n<\/div>\n
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          CREATE TABLE<\/span> City_Pt (\r\n    ID int NOT NULL,\r\n    Name varchar<\/span>(255) NOT NULL,\r\n    Geom_Point varchar<\/span>(255),\r\n    CityID int FOREIGN KEY REFERENCES City_Info<\/span>(CityID )\r\n);<\/span><\/code><\/strong><\/pre>\n<\/figure>\n<\/div>\n<\/div>\n
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          City_Poly – Fields – Geom (Polygon), ID, Name, CityID (Foreign Key)<\/p>\n<\/div>\n<\/div>\n
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          CREATE TABLE<\/span> City_Poly (\r\n    ID int NOT NULL,\r\n    Name varchar<\/span>(255) NOT NULL,\r\n    Geom_Polygon varchar<\/span>(255),\r\n    CityID int FOREIGN KEY REFERENCES City_Info<\/span>(CityID )\r\n);<\/strong><\/span><\/code><\/pre>\n<\/figure>\n<\/div>\n<\/div>\n
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          This is the one of the ways of setting up the database, again it depends on your specific needs for being able to link different pieces of data together.<\/p>\n
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          Once the table structure is determined, the next part will be to set up queries to retrieve the information you want, for inclusion in a report or some sort of viewing application.<\/li>\n<\/ul>\n<\/div>\n<\/div>\n","protected":false},"excerpt":{"rendered":"
          Answer : Hierarchical data is a common relational data pattern for representing tree-like data structures…<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"passster_activate_protection":false,"passster_protect_child_pages":"","passster_protection_type":"password","passster_password":"","passster_activate_overwrite_defaults":"","passster_headline":"","passster_instruction":"","passster_placeholder":"","passster_button":"","passster_id":"","passster_activate_misc_settings":"","passster_redirect_url":"","passster_hide":"no","passster_area_shortcode":"","gtb_hide_title":false,"gtb_wrap_title":false,"gtb_class_title":"","gtb_remove_headerfooter":false,"footnotes":""},"categories":[7157],"tags":[195,7247,7254,7249,7244,360,203,199,214,7252,198,363,209,15936,205,7233,7250,222,7251,7238,7232,7241,7237,7235,7234,7253,7239,7245,7248,7243,7240,7236,196,212,213,286,710,207,366,204,282,208,367,3715,206,7207,200,197,280,364,7242,7246,285],"class_list":["post-1037","post","type-post","status-publish","format-standard","hentry","category-dbms","tag-accenture-interview-questions-and-answers","tag-advantages-and-disadvantages-of-hierarchical-model","tag-advantages-and-disadvantages-of-hierarchical-structure","tag-advantages-of-hierarchical-model","tag-advantages-of-hierarchical-structure","tag-atos-interview-questions-and-answers","tag-capgemini-interview-questions-and-answers","tag-casting-networks-india-pvt-limited-interview-questions-and-answers","tag-cgi-group-inc-interview-questions-and-answers","tag-characteristics-of-hierarchical-database-model","tag-chetu-interview-questions-and-answers","tag-ciena-corporation-interview-questions-and-answers","tag-collabera-technologies-interview-questions-and-answers","tag-dawnbit-interview-questions-and-answers","tag-dell-international-services-india-pvt-ltd-interview-questions-and-answers","tag-ehierarchical-data-model","tag-explain-hierarchical-data-model-with-example","tag-flipkart-interview-questions-and-answers","tag-hierarchical-data-model-example","tag-hierarchical-data-structure","tag-hierarchical-databas","tag-hierarchical-database-advantages-and-disadvantages","tag-hierarchical-database-example","tag-hierarchical-database-model","tag-hierarchical-database-model-advantages-and-disadvantages","tag-hierarchical-database-model-diagram","tag-hierarchical-model","tag-hierarchical-model-advantages-and-disadvantages","tag-hierarchical-model-example","tag-hierarchical-queriesdis","tag-hierarchical-structure-definition","tag-hierarchical-structure-example","tag-ibm-interview-questions-and-answers","tag-indecomm-global-services-interview-questions-and-answers","tag-infosys-technologies-interview-questions-and-answers","tag-lt-infotech-interview-questions-and-answers","tag-mavenir-interview-questions-and-answers","tag-mphasis-interview-questions-and-answers","tag-netapp-interview-questions-and-answers","tag-oracle-corporation-interview-questions-and-answers","tag-persistent-systems-interview-questions-and-answers","tag-prokarma-softech-pvt-ltd-interview-questions-and-answers","tag-rbs-india-development-centre-pvt-ltd-interview-questions-and-answers","tag-ruboid-technovision-pvt-ltd-interview-questions-and-answers","tag-sap-labs-india-pvt-ltd-interview-questions-and-answers","tag-shell-infotech-interview-questions-and-answers","tag-tech-mahindra-interview-questions-and-answers","tag-unitedhealth-group-interview-questions-and-answers","tag-virtusa-consulting-services-pvt-ltd-interview-questions-and-answers","tag-wells-fargo-interview-questions-and-answers","tag-what-is-hierarchical-database","tag-what-is-hierarchical-model","tag-xoriant-solutions-pvt-ltd-interview-questions-and-answers"],"yoast_head":"\n