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
As per the documentation: FROM (Transact-SQL): <join_type> ::= [ { INNER | { { LEFT | RIGHT | FULL } [ OUTER ] } } [ <join_hint> ] ] JOIN The keyword OUTER is marked as optional (enclosed in square brackets). In this specific case, whether you specify OUTER or not makes no difference. Note … Read more
Reading this original article on The Code Project will help you a lot: Visual Representation of SQL Joins. Also check this post: SQL SERVER – Better Performance – LEFT JOIN or NOT IN?. Find original one at: Difference between JOIN and OUTER JOIN in MySQL.
Assuming you’re joining on columns with no duplicates, which is a very common case: An inner join of A and B gives the result of A intersect B, i.e. the inner part of a Venn diagram intersection. An outer join of A and B gives the results of A union B, i.e. the outer parts … Read more
Something like x <- 1:20; names(x) <-x y <- c(0.05, 0.025, 0.01, 0.005, 0.001, 0.0005); names(y) <- y outer(x, y,function(x, y) {abs(qt(y, df=x))}) #> 0.05 0.025 0.01 0.005 0.001 5e-04 #> 1 6.313752 12.706205 31.820516 63.656741 318.308839 636.619249 #> 2 2.919986 4.302653 6.964557 9.924843 22.327125 31.599055 #> 3 2.353363 3.182446 4.540703 5.840909 10.214532 12.923979 #> … Read more