Upload 172

Author: ggeerraarrdd

README.md

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 [![eevveerryyddaayy release](https://img.shields.io/badge/eevveerryyddaayy-v1.3.0-blue.svg)](https://github.com/ggeerraarrdd/eevveerryyddaayy/)
-[![Solved](https://img.shields.io/badge/solved-171-green.svg)](#index)
+[![Solved](https://img.shields.io/badge/solved-172-green.svg)](#index)
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 # SQL Everyday
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 | 169   | [NPV Queries](https://leetcode.com/problems/npv-queries/description/)                                                                                             | [Solution](solutions/169_npv_queries.md)                                                | LeetCode    | Easy         |                                                                     |
 | 170   | [Game Play Analysis II](https://leetcode.com/problems/game-play-analysis-ii/description/)                                                                         | [Solution](solutions/170_game_play_analysis_ii.md)                                      | LeetCode    | Easy         |                                                                     |
 | 171   | [Total Traveled Distance](https://leetcode.com/problems/total-traveled-distance/description/)                                                                     | [Solution](solutions/171_total_traveled_distance.md)                                    | LeetCode    | Easy         |                                                                     |
+| 172   | [Create a Session Bar Chart](https://leetcode.com/problems/create-a-session-bar-chart/description/)                                                               | [Solution](solutions/172_create_a_session_bar_chart.md)                                 | LeetCode    | Easy         | Histogram bins w/ `UNION`, `CASE`                                   |
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solutions/172_create_a_session_bar_chart.md

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+# SQL Everyday \#172
+
+## Create a Session Bar Chart
+
+Site: LeetCode\
+Difficulty per Site: Easy
+
+## Problem
+
+You want to know how long a user visits your application. You decided to create bins of `"[0-5>"`, `"[5-10>"`, `"[10-15>"`, and `"15 minutes or more"` and count the number of sessions on it.
+
+Write a solution to report the `(bin, total)`.
+
+Return the result table in *any order*. [[Full Description](https://leetcode.com/problems/create-a-session-bar-chart/description/)]
+
+## Submitted Solution
+
+```sql
+-- Submitted Solution
+WITH cte1 AS (
+    SELECT '[0-5>' AS bin FROM Sessions
+    UNION
+    SELECT '[5-10>' AS bin FROM Sessions
+    UNION
+    SELECT '[10-15>' AS bin FROM Sessions
+    UNION
+    SELECT '15 or more' AS bin FROM Sessions
+),
+cte2 AS (
+SELECT
+    CASE WHEN (duration/60) < 5 THEN '[0-5>' 
+         WHEN (duration/60) < 10 THEN '[5-10>'
+         WHEN (duration/60) < 15 THEN '[10-15>' 
+         ELSE '15 or more' END AS bin
+FROM Sessions
+)
+SELECT
+    c1.bin
+    ,COALESCE(COUNT(c2.bin), 0) AS total
+FROM cte1 AS c1
+LEFT JOIN cte2 AS c2 ON c1.bin = c2.bin
+GROUP BY c1.bin
+;
+```
+
+## Site Solution
+
+```sql
+-- LeetCode Solution 
+-- None
+```
+
+## Notes
+
+This is easy enough with `CASE` and `GROUP BY`. But the not-so easy part is ensuring any missing bin is also counted as 0.
+
+## NB
+
+Histogram bins w/ `UNION`, `CASE`
+
+Go to [Index](../?tab=readme-ov-file#index)\
+Go to [Overview](../?tab=readme-ov-file)