If you join a team project, you have to follow the team convention. It is not necessary to put dbo. in front of table names in SQL server. Yes, you can use .PHP instead of .INC for class files. No, C# will compile just fine if you indent with four spaces or eight spaces instead of a tab.

However, when you are working in a team, you follow the convention of the team. Or change the convention so the team is on the same page.

>It is not necessary to put dbo. in front of table names in SQL server.

Depending on default schema, it definitely can have performance considerations on compilation.

Maybe some of those team conventions are actually based on real world things.

From: https://msdn.microsoft.com/en-us/library/dd283095%28v=sql.10...

SELECT * FROM Table1

Will assess the following statement first: SELECT * FROM <defaultschema>.Table1

If it cannot find the object, the server will assess the following statement: SELECT * FROM dbo.Table1.

The assessment process can be improved by using either the fully qualified name or the DEFAULT_SCHEMA option described earlier. By setting a value for DEFAULT_SCHEMA for the user, the server will check the DEFAULT_SCHEMA first, removing an unnecessary ownership checking process. This can improve performance considerably on heavily utilized systems.

The point is not the existence of conventions but the correct and wise application of them as opposed to just "let's do what the internet blogs about!".

Critical thinking will never be out of style, no matter how much people try.