Joins allow you to combine data from multiple tables.
```SQL
SELECT *
FROM <table1>
JOIN <table2> ON <table1.field> = <table2.field>;
```
An equivalent syntax (sometimes referred to as an **implicit** join) is
```SQL
SELECT *
FROM <table1> A, <table2> B
WHERE A.<field> = B.<field>
```
Be wary of creating a [[Cartesian product]] during a join.
## outer join
An outer join will include all the rows from the LEFT or RIGHT table even if the keys don't match. This is useful when you want to make sure you have all of the records from the first table when joining the second table even if the record does not have a match in the second table.
## inner join