# 1378. Replace Employee ID With The Unique Identifier

<https://leetcode.com/problems/replace-employee-id-with-the-unique-identifier>

## Description

Table: `Employees`

```
+---------------+---------+
| Column Name   | Type    |
+---------------+---------+
| id            | int     |
| name          | varchar |
+---------------+---------+
id is the primary key for this table.
Each row of this table contains the id and the name of an employee in a company.
```

Table: `EmployeeUNI`

```
+---------------+---------+
| Column Name   | Type    |
+---------------+---------+
| id            | int     |
| unique\_id     | int     |
+---------------+---------+
(id, unique\_id) is the primary key for this table.
Each row of this table contains the id and the corresponding unique id of an employee in the company.
```

Write an SQL query to show the **unique ID** of each user, If a user doesn't have a unique ID replace just show null.

Return the result table in **any** order.

The query result format is in the following example:

```
Employees table:
+----+----------+
| id | name     |
+----+----------+
| 1  | Alice    |
| 7  | Bob      |
| 11 | Meir     |
| 90 | Winston  |
| 3  | Jonathan |
+----+----------+
EmployeeUNI table:
+----+-----------+
| id | unique\_id |
+----+-----------+
| 3  | 1         |
| 11 | 2         |
| 90 | 3         |
+----+-----------+
Result table:
+-----------+----------+
| unique\_id | name     |
+-----------+----------+
| null      | Alice    |
| null      | Bob      |
| 2         | Meir     |
| 3         | Winston  |
| 1         | Jonathan |
+-----------+----------+
Alice and Bob don't have a unique ID, We will show null instead.
The unique ID of Meir is 2.
The unique ID of Winston is 3.
The unique ID of Jonathan is 1.
```

## ac

```java
```