Opposite Of An Inner Join Query
Select * from table1 left join table2 on table1.id = table2.id where table2.id is null
Select * from table1 left join table2 on table1.id = table2.id where table2.id is null
They are the same thing in MySQL. A LEFT JOIN is a synonym or shorthand for LEFT OUTER JOIN.
SELECT p.pid, p.cid, p.pname, c1.name1, c2.name2 FROM product p LEFT JOIN customer1 c1 ON p.cid = c1.cid LEFT JOIN customer2 c2 ON p.cid = c2.cid
Try This SELECT f.* FROM first_table f LEFT JOIN second_table s ON f.key=s.key WHERE s.key is NULL For more please read this article : Joins in Sql Server
There is no difference between RIGHT JOIN and RIGHT OUTER JOIN. Both are the same. That means that LEFT JOIN and LEFT OUTER JOIN are the same. Visual Representation of SQL Joins
Use OUTER APPLY instead of LEFT JOIN: SELECT u.id, mbg.marker_value FROM dps_user u OUTER APPLY (SELECT TOP 1 m.marker_value, um.profile_id FROM dps_usr_markers um (NOLOCK) INNER JOIN dps_markers m (NOLOCK) ON m.marker_id= um.marker_id AND m.marker_key = ‘moneyBackGuaranteeLength’ WHERE um.profile_id=u.id ORDER BY m.creation_date ) AS MBG WHERE u.id = ‘u162231993’; Unlike JOIN, APPLY allows you to reference … Read more
You need to introduce your join condition before calling DefaultIfEmpty(). I would just use extension method syntax: from p in context.Periods join f in context.Facts on p.id equals f.periodid into fg from fgi in fg.Where(f => f.otherid == 17).DefaultIfEmpty() where p.companyid == 100 select f.value Or you could use a subquery: from p in context.Periods … Read more
That’s Oracle specific notation for an OUTER JOIN, because the ANSI-89 format (using a comma in the FROM clause to separate table references) didn’t standardize OUTER joins. The query would be re-written in ANSI-92 syntax as: SELECT … FROM a LEFT JOIN b ON b.id = a.id This link is pretty good at explaining the … Read more
Update 1: providing a truly generalized extension method FullOuterJoin Update 2: optionally accepting a custom IEqualityComparer for the key type Update 3: this implementation has recently become part of MoreLinq – Thanks guys! Edit Added FullOuterGroupJoin (ideone). I reused the GetOuter<> implementation, making this a fraction less performant than it could be, but I’m aiming … Read more
You don’t have full joins in MySQL, but you can sure emulate them. For a code sample transcribed from this Stack Overflow question you have: With two tables t1, t2: SELECT * FROM t1 LEFT JOIN t2 ON t1.id = t2.id UNION SELECT * FROM t1 RIGHT JOIN t2 ON t1.id = t2.id The query above … Read more