The fact that when it says INNER JOIN, you can be sure of what it does and that it's supposed to be just that, whereas a plain JOIN will leave you, or someone else, wondering what the standard said about …

The question and solutions pertain specifically to INNER JOINs. If the join is a LEFT/RIGHT/FULL OUTER JOIN, then it is not a matter of preference or performance, but one of correct results. The …

The first query employs some lesser-known ANSI SQL syntax which allows you to nest joins between the join and on clauses. This allows you to scope/tier your joins and probably opens up a host of …

Do you really want to be able to join the tables if a value is null? Can't you just exclude the possible null values in the join predicate? I find it hard to grok that rows in two tables can be related by a null value.

In most INNER JOIN queries (one-to-many relationships), I could rewrite them to use CROSS APPLY, but they always give me equivalent execution plans. Can anyone give me a good example of when …

Theta-join is analogous to a special case of inner join where the on is a theta comparison on of a column from each. Some decades after Codd defined them some textbook (s) misdefined theta join as a …

left_join(x, y, by = c("a" = "b") will match x.a to y.b However, is it possible to join on a combination of variables or do I have to add a composite key beforehand?

The inner join will return data only if there is a match between both tables. The left join will return data from the first table regardless if a matching record is found in the second table.

This was an example, but the point is as Eric said in How can I do an UPDATE statement with JOIN in SQL Server?. You need to add an UPDATE statement at first with the full address of all tables to join …

Compare these 2 queries. Is it faster to put the filter on the join criteria or in the WHERE clause. I have always felt that it is faster on the join criteria because it reduces the result set at the