![]() In this example, it was required because studentID is the same column name in both tables, and the system would present an “ambiguous column name error” without specifying which table to use. It’s easier than typing long table names repeatedly. This is a tool to shorten the table names and make it easier to identify which table is being used. Notice the “alias” given to each table (“s” for student and “sc” for student contact).To “join” tables, the tables must have fields in common (usually primary keys) that uniquely identity each row.Sample of using a View to combine data from more than one tableĪ Student demographics table was added to the database to demonstrate this usage. the ”`” character around the view names is required because of the ”-” in the names.The columns in the view are limited by the SELECT and the rows of data by the WHERE clause.Your IT shop should have its own rules on naming objects. It’s recommended that the view name indicate that it’s a view in some way to make life easier for programmers and database administrators. The name of the view has a “v” at the end.Sample View creation from the student tables This guide will cover this part of of the statement… CREATE Syntax of the Create View Statement (MySQL) CREATE Spend time with your database managers manual and have fun with this powerful SQL object. There are many other details about views that are beyond the scope of this introductory guide.Views can usually be treated as you would a table, but updates are limited or not available when the view contains more than one table.The others are tables, stored procedures, and functions. Views are one of the four standard database object types.The view would have to be updated or recreated. In MySQL, changes to the table design (that is, new or dropped columns) made AFTER a view is created are not updated in the view itself.We want to use these only when needed to manage use of system resources. When data in the related tables are changed, added, or updated, the View is updated by the system. Complex data across more than one table can be combined into a single “view.” This can make life easier for your business analysts and programmers.Sensitive information in this case could be social security numbers, sex of employee, payrate, home address, etc. For example, the human resources department data filtered to only present sensitive information. ![]() Views are a way to limit the data presented. There is a strange rule in MySql which basically says if you want to create a view and you want to use constructs such as GROUP BY, DISTINCT, UNION, etc.They just “point” to the data that exists elsewhere (tables or views, for example). Views are used in a similar way to tables, but they don’t contain any data. A View is a database object that presents data existing in one or more tables.
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