Problem 1: Triangle Judgement

SQL Schema

Table: Triangle

+-------------+------+
| Column Name | Type |
+-------------+------+
| x           | int  |
| y           | int  |
| z           | int  |
+-------------+------+
(x, y, z) is the primary key column for this table.
Each row of this table contains the lengths of three line segments.

 

Write an SQL query to report for every three-line segments whether they can form a triangle.

Return the result table in any order.

The query result format is in the following example.

 

Example 1:

Input:
Triangle table:
+----+----+----+
| x  | y  | z  |
+----+----+----+
| 13 | 15 | 30 |
| 10 | 20 | 15 |
+----+----+----+
Output:
+----+----+----+----------+
| x  | y  | z  | triangle |
+----+----+----+----------+
| 13 | 15 | 30 | No       |
| 10 | 20 | 15 | Yes      |
+----+----+----+----------+

 

SELECT x, y, z,

CASE

WHEN x + y > z AND  y + z > x AND x + z > y THEN 'Yes'

ELSE 'No'

END AS `triangle`

FROM Triangle;

Case 1

Input

Triangle =

| x | y | z | | -- | -- | -- | | 13 | 15 | 30 | | 10 | 20 | 15 |

Output

| x | y | z | triangle | | -- | -- | -- | -------- | | 13 | 15 | 30 | No | | 10 | 20 | 15 | Yes |