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 of a Venn diagram union.

**Examples**

Suppose you have two tables, with a single column each, and data as follows:

```
A B
- -
1 3
2 4
3 5
4 6
```

Note that (1,2) are unique to A, (3,4) are common, and (5,6) are unique to B.

**Inner join**

An inner join using either of the equivalent queries gives the intersection of the two tables, i.e. the two rows they have in common.

```
select * from a INNER JOIN b on a.a = b.b;
select a.*, b.* from a,b where a.a = b.b;
a | b
--+--
3 | 3
4 | 4
```

**Left outer join**

A left outer join will give all rows in A, plus any common rows in B.

```
select * from a LEFT OUTER JOIN b on a.a = b.b;
select a.*, b.* from a,b where a.a = b.b(+);
a | b
--+-----
1 | null
2 | null
3 | 3
4 | 4
```

**Right outer join**

A right outer join will give all rows in B, plus any common rows in A.

```
select * from a RIGHT OUTER JOIN b on a.a = b.b;
select a.*, b.* from a,b where a.a(+) = b.b;
a | b
-----+----
3 | 3
4 | 4
null | 5
null | 6
```

**Full outer join**

A full outer join will give you the union of A and B, i.e. all the rows in A and all the rows in B. If something in A doesn't have a corresponding datum in B, then the B portion is null, and vice versa.

```
select * from a FULL OUTER JOIN b on a.a = b.b;
a | b
-----+-----
1 | null
2 | null
3 | 3
4 | 4
null | 6
null | 5
```

Convert a number to a hexadecimal string with:

```
hexString = yourNumber.toString(16);
```

And reverse the process with:

```
yourNumber = parseInt(hexString, 16);
```

## Best Solution

Convert INT to hex:

Convert hex to INT:

## Update 2015-03-16

The above example has the limitation that it only works when the HEX value is given as an integer literal. For completeness, if the value to convert is a hexadecimal string (such as found in a varchar column) use:

Note:The string must contain an even number of hex digits. An odd number of digits will yield an error.More details can be found in the "Binary Styles" section of CAST and CONVERT (Transact-SQL). I believe SQL Server 2008 or later is required.