This keeps the legacy code that references the table from breaking, allowing you to change the legacy code at your leisure. The view provides the exact same schema as the original table, while the actual schema has changed. If you need to refactor a table that would break a lot of code, you can replace the table with a view of the same name. Views can simplify supporting legacy code.This allows surfacing only the data that a user needs to see. I know subsonic can provide a newest list which orders by release date but that’s not what I’m using there. I’ll rename it as recently added so it’s clearer. Views can be used as a security mechanismĪ view can select certain columns and/or rows from a table (or tables), and permissions set on the view instead of the underlying tables. That newest albums section on the home screen is actually the recently added list.If you have a query that requires joining several tables, or has complex logic or calculations, you can code all that logic into a view, then select from the view just like you would a table. Want to improve the above article? Contribute your Notes/Comments/Examples through Disqus. Here is a new document which is a collection of questions with short and simple answers, useful for learning SQL as well as for interviews. Output: CUST_CITY CUST_COUNTRY MIN(OUTSTANDING_AMT) The following SQL statement can be used: SELECT cust_city, cust_country, 'cust_city' and 'cust_country' should be formatted in a group, To get data of 'cust_city', 'cust_country' and minimum or lowest value of 'outstanding_amt' from the 'customer' table with following conditions -ġ.
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