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1 |
| ---1378. Replace Employee ID With The Unique Identifier |
2 |
| --- |
3 |
| ---Table: Employees |
4 |
| --- |
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| ---+---------------+---------+ |
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| ---| Column Name | Type | |
7 |
| ---+---------------+---------+ |
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| ---| id | int | |
9 |
| ---| name | varchar | |
10 |
| ---+---------------+---------+ |
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| ---id is the primary key for this table. |
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| ---Each row of this table contains the id and the name of an employee in a company. |
13 |
| --- |
14 |
| --- |
15 |
| ---Table: EmployeeUNI |
16 |
| --- |
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| ---+---------------+---------+ |
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| ---| Column Name | Type | |
19 |
| ---+---------------+---------+ |
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| ---| id | int | |
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| ---| unique_id | int | |
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| ---+---------------+---------+ |
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| ---(id, unique_id) is the primary key for this table. |
24 |
| ---Each row of this table contains the id and the corresponding unique id of an employee in the company. |
25 |
| --- |
26 |
| --- |
27 |
| ---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. |
28 |
| --- |
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| ---Return the result table in any order. |
30 |
| --- |
31 |
| ---The query result format is in the following example: |
32 |
| --- |
33 |
| ---Employees table: |
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| ---+----+----------+ |
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| ---| id | name | |
36 |
| ---+----+----------+ |
37 |
| ---| 1 | Alice | |
38 |
| ---| 7 | Bob | |
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| ---| 11 | Meir | |
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| ---| 90 | Winston | |
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| ---| 3 | Jonathan | |
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| ---+----+----------+ |
43 |
| --- |
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| ---EmployeeUNI table: |
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| ---+----+-----------+ |
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| ---| id | unique_id | |
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| ---+----+-----------+ |
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| ---| 3 | 1 | |
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| ---| 11 | 2 | |
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| ---| 90 | 3 | |
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| ---+----+-----------+ |
52 |
| --- |
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| ---EmployeeUNI table: |
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| ---+-----------+----------+ |
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| ---| unique_id | name | |
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| ---+-----------+----------+ |
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| ---| null | Alice | |
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| ---| null | Bob | |
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| ---| 2 | Meir | |
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| ---| 3 | Winston | |
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| ---| 1 | Jonathan | |
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| ---+-----------+----------+ |
63 |
| --- |
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| ---Alice and Bob don't have a unique ID, We will show null instead. |
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| ---The unique ID of Meir is 2. |
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| ---The unique ID of Winston is 3. |
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| ---The unique ID of Jonathan is 1. |
68 |
| --- |
69 | 1 | --# Write your MySQL query statement below
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70 | 2 |
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71 | 3 | select uni.unique_id, emp.name from Employees emp
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