Update ch08: 秋招秘籍 C.md

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2021-08-29 18:15:36 +08:00
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@@ -1,9 +1,9 @@
# 练习一:行转列
假设有如下比赛结果
```plain
+------------+-----------+
| cdate | result |
+------------+-----------+
+--------------+-----------+
| cdate | result |
+--------------+-----------+
| 2021-01-01 | 胜 |
| 2021-01-01 | 负 |
| 2021-01-03 | 胜 |
@@ -14,9 +14,9 @@
```
请使用 SQL 将比赛结果转换为如下形式:
```plain
+------------+-----+-----|
| 比赛日期 | 胜 | 负 |
+------------+-----------+
+--------------+-----+-----|
| 比赛日期 | 胜 | 负 |
+--------------+-----------+
| 2021-01-01 | 2 | 1 |
| 2021-01-03 | 1 | 2 |
+------------+-----------+
@@ -24,18 +24,18 @@
# 练习二:列转行
假设有如下比赛结果
```plain
+------------+-----+-----|
| 比赛日期 | 胜 | 负 |
+------------+-----------+
+--------------+-----+-----|
| 比赛日期 | 胜 | 负 |
+--------------+-----------+
| 2021-01-01 | 2 | 1 |
| 2021-01-03 | 1 | 2 |
+------------+-----------+
```
请使用 SQL 将比赛结果转换为如下形式:
```plain
+------------+-----------+
| cdate | result |
+------------+-----------+
+--------------+-----------+
| cdate | result |
+--------------+-----------+
| 2021-01-01 | 胜 |
| 2021-01-01 | 负 |
| 2021-01-03 | 胜 |