drop index

data/2.MySQL中阶/5. 索引/1.索引入门/config.json

 {
   "node_id": "mysql-bf629829370d405cbfcd5aa83adb536a",
-  "keywords": [],
+  "keywords": ["index", "index"],
   "children": [],
-  "export": [],
+  "export": [
+    "index.json"
+  ],
   "keywords_must": [
-    ["mysql", "索引", "入门"]
+    [
+      "mysql",
+      "索引",
+      "入门"
+    ]
   ],
   "keywords_forbid": [],
-  "group": 0
+  "group": 1
 }
\ No newline at end of file

data/2.MySQL中阶/5. 索引/1.索引入门/index.json

+{
+  "type": "code_options",
+  "author": "ccat",
+  "source": "index.md",
+  "notebook_enable": false,
+  "exercise_id": "ac49bba4d8fc428b90c8773b07b6ec65"
+}
\ No newline at end of file

data/2.MySQL中阶/5. 索引/1.索引入门/index.md

+# 索引
+
+关于 MySQL 的索引，一下说法正确的是：
+
+1. 索引可以指定不同的格式，以满足不同的性能需求
+2. 索引可以伴有唯一约束
+3. 主键会自动包含聚集索引
+4. 聚集索引只能应用于自增字段
+5. 索引可以基于一个或多个字段
+6. 可以创建函数或表达式索引
+7. MySQL 支持全文索引（Full Text Index）
+
+## 答案
+
+```
+1, 2, 3, 5, 6, 7
+```
+
+## 选项
+
+### A
+
+全部都对
+
+### B
+
+全部都错
+
+### C
+
+```
+1, 2, 3, 4
+```
+
+### D
+
+```
+4, 5, 6, 7
+```
+
+### E
+
+```
+2, 4, 6, 8
+```
\ No newline at end of file

data/2.MySQL中阶/5. 索引/2.创建索引/config.json

 {
   "node_id": "mysql-fe65d5c615ad40f8ac056cc654f2d788",
-  "keywords": [],
+  "keywords": ["create index", "创建索引"],
   "children": [],
-  "export": [],
+  "export": [
+    "create_index.json"
+  ],
   "keywords_must": [
-    ["mysql", "创建", "索引"]
+    [
+      "mysql",
+      "创建",
+      "索引"
+    ]
   ],
   "keywords_forbid": [],
-  "group": 0
+  "group": 1
 }
\ No newline at end of file

data/2.MySQL中阶/5. 索引/2.创建索引/create_index.json

+{
+  "type": "code_options",
+  "author": "ccat",
+  "source": "create_index.md",
+  "notebook_enable": false,
+  "exercise_id": "6b84238a23d24623a32c416016075701"
+}
\ No newline at end of file

data/2.MySQL中阶/5. 索引/2.创建索引/create_index.md

+# 创建索引
+
+Joe 想给 Goods 表
+
+```mysql
+create table goods(
+    id int primary key auto_increment,
+    category_id int,
+    name varchar(256),
+    price decimal(12, 4),
+    stock int,
+    upper_time timestamp
+)
+```
+
+的 category_id （类别）字段创建索引，便于根据类别查询商品。应该执行下面哪个语句？
+
+*注意* 一个类别会包含多种商品。
+
+## 答案
+
+```mysql
+create index idx_goods_category on goods(category_id);
+```
+
+## 选项
+
+### A
+
+```mysql
+create unique index idx_goods_category on goods(category_id);
+```
+
+### B
+
+```mysql
+create index idx_goods_category on goods(category_id);
+```
+
+### C
+
+```mysql
+alter table goods add unique index (category_id);
+```
\ No newline at end of file

data/2.MySQL中阶/5. 索引/3.删除索引/config.json

 {
   "node_id": "mysql-85ba0df78d754b00b30aa8e74ad35d06",
-  "keywords": [],
+  "keywords": [
+    "删除索引",
+    "drop index"
+  ],
   "children": [],
-  "export": [],
+  "export": [
+    "drop_index.json"
+  ],
   "keywords_must": [
-    ["mysql", "删除", "索引"]
+    [
+      "mysql",
+      "删除",
+      "索引"
+    ]
   ],
   "keywords_forbid": [],
-  "group": 0
+  "group": 1
 }
\ No newline at end of file

data/2.MySQL中阶/5. 索引/3.删除索引/drop_index.json

+{
+  "type": "code_options",
+  "author": null,
+  "source": "drop_index.md",
+  "notebook_enable": false,
+  "exercise_id": "f786df4790e0407b91348a0fad24220f"
+}
\ No newline at end of file

data/2.MySQL中阶/5. 索引/3.删除索引/drop_index.md

+# 删除索引
+
+Joe 想要删除创建在 goods 表创建的索引，但是他已经忘了这个索引的名字，那么他应该怎么做？
+
+## 答案
+
+执行
+
+```mysql
+show index from goods;
+```
+
+查看 goods 表的索引（假设查到是 idx_goods_category），然后执行
+
+```mysql
+alter table goods drop index idx_goods_category;
+```
+
+## 选项
+
+### A
+
+执行
+
+```mysql
+show index from goods;
+```
+
+查看 goods 表的索引（假设查到是 idx_goods_category），然后执行
+
+```mysql
+alter table goods delete index idx_goods_category;
+```
+
+### B
+
+执行
+
+```mysql
+show index from goods;
+```
+
+查看 goods 表的索引（假设查到是 idx_goods_category），然后执行
+
+```mysql
+alter table goods remove index idx_goods_category;
+```
+
+### C
+
+执行
+
+```mysql
+show index from goods;
+```
+
+查看 goods 表的索引（假设查到是 idx_goods_category），然后执行
+
+```mysql
+alter table goods drop idx_goods_category;
+```
+
+
+
+

data/2.MySQL中阶/6.子查询/6. 列子查询/in_column.json

 {
   "type": "code_options",
-  "author": null,
+  "author": "Mars",
   "source": "in_column.md",
   "notebook_enable": false,
   "exercise_id": "464fd8f686284280afbee9424ed4ae65"

data/tree.json

@@ -1098,7 +1098,10 @@
                   {
                     "索引入门": {
                       "node_id": "mysql-bf629829370d405cbfcd5aa83adb536a",
-                      "keywords": [],
+                      "keywords": [
+                        "index",
+                        "index"
+                      ],
                       "children": [],
                       "keywords_must": [
                         [
@@ -1108,13 +1111,16 @@
                         ]
                       ],
                       "keywords_forbid": [],
-                      "group": 0
+                      "group": 1
                     }
                   },
                   {
                     "创建索引": {
                       "node_id": "mysql-fe65d5c615ad40f8ac056cc654f2d788",
-                      "keywords": [],
+                      "keywords": [
+                        "create index",
+                        "创建索引"
+                      ],
                       "children": [],
                       "keywords_must": [
                         [
@@ -1124,13 +1130,16 @@
                         ]
                       ],
                       "keywords_forbid": [],
-                      "group": 0
+                      "group": 1
                     }
                   },
                   {
                     "删除索引": {
                       "node_id": "mysql-85ba0df78d754b00b30aa8e74ad35d06",
-                      "keywords": [],
+                      "keywords": [
+                        "删除索引",
+                        "drop index"
+                      ],
                       "children": [],
                       "keywords_must": [
                         [
@@ -1140,7 +1149,7 @@
                         ]
                       ],
                       "keywords_forbid": [],
-                      "group": 0
+                      "group": 1
                     }
                   }
                 ],