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Why does MySQL not support full outer join?
MySQL doesn’t offer syntax for a full outer join, but you can implement one using the union of a left and a right join. Since no indexes are likely to be used, expect for these results to take a long time on tables of any significant size.
What is the alternate option to achieve full outer join?
The alternative is a 3-part UNION, i.e. It must be fine to use Full Outer Join.
How do I get full outer join in MySQL?
However, as Pablo Santa Cruz pointed out, MySQL doesn’t support this. We can emulate it by doing a UNION of a left join and a right join, like this: SELECT * FROM `t1` LEFT OUTER JOIN `t2` ON `t1`.
How does full outer join works?
In SQL the FULL OUTER JOIN combines the results of both left and right outer joins and returns all (matched or unmatched) rows from the tables on both sides of the join clause. Let’s combine the same two tables using a full join. Here is an example of full outer join in SQL between two tables.
When to use full outer join or left join?
An outer join includes elements from a for which no corresponding element exists in b. (i.e.: even results if b were empty). This is usually referred to as left join. A full outer join includes records from a as well as b if no corresponding element exists in the other.
Is there a FULL OUTER JOIN in MySQL?
So far as I know, you can’t do a full outer join in MySQL, so just run it as the UNION of a LEFT JOIN and a RIGHT JOIN as I think this would fix your problem. EDIT: After a quick Googling, I realized that the above may not be perfect for all cases. Instead you could do See this blog post for reference.
Is there an outer join construct in LINQ?
With this fix, it now seems the return behavior is in line with my goals after all. As you’ve found, Linq doesn’t have an “outer join” construct. The closest you can get is a left outer join using the query you stated. To this, you can add any elements of the lastname list that aren’t represented in the join: