operator

data/1.MySQL初阶/5.数据修改/2.修改/config.json

@@ -2,7 +2,9 @@
   "node_id": "mysql-2eb9e9d351e848f580b70cf9e7b93280",
   "keywords": [],
   "children": [],
-  "export": [],
+  "export": [
+    "update.json"
+  ],
   "keywords_must": [],
   "keywords_forbid": [],
   "group": 0

data/1.MySQL初阶/5.数据修改/2.修改/update.json

+{
+  "type": "code_options",
+  "author": "ccat",
+  "source": "update.md",
+  "notebook_enable": false,
+  "exercise_id": "cf4476a1954440b499c84e022ec463ea"
+}
\ No newline at end of file

data/1.MySQL初阶/5.数据修改/2.修改/update.md

+# 更新数据
+
+现有 employee 表如下：
+
+```mysql
+create table employee
+(
+    id serial primary key,
+    name text,
+    dept text,
+    salary money
+);
+```
+
+Joe 希望修改销售部(dept 字段为 sale)员工 Dora Muk 的工资，将其增加 1000。正确的修改语句是：
+
+## 答案
+
+```mysql
+update employee set salary = salary + 1000 where dept = 'sale' and name = 'Dora Muk';
+```
+
+## 选项
+
+### 过滤条件不严谨
+
+```mysql
+update employee set salary = salary + 1000 where name = 'Dora Muk';
+```
+
+
+### 缺少过滤条件
+
+```mysql
+update employee set salary = salary + 1000;
+```
+
+### 错误的赋值语句
+
+```mysql
+update employee set salary += 1000;
+```
+

data/1.MySQL初阶/5.数据修改/3.删除/config.json

@@ -2,7 +2,9 @@
   "node_id": "mysql-3cae643e21644d6d937d69b59014922f",
   "keywords": [],
   "children": [],
-  "export": [],
+  "export": [
+    "delete.json"
+  ],
   "keywords_must": [],
   "keywords_forbid": [],
   "group": 0

data/1.MySQL初阶/5.数据修改/3.删除/delete.json

+{
+  "type": "code_options",
+  "author": "ccat",
+  "source": "delete.md",
+  "notebook_enable": false,
+  "exercise_id": "cfdd2c9789fd4fe493541cfa8811e4c9"
+}
\ No newline at end of file

data/1.MySQL初阶/5.数据修改/3.删除/delete.md

+# 删除
+
+现在 orders 表结构如下：
+
+```mysql
+create table orders (
+                        id int primary key auto_increment,
+                        item_id int,
+                        amount int,
+                        unit_price decimal(12, 4),
+                        total_price decimal(12, 4),
+                        description varchar(2000),
+                        ts timestamp default now(),
+                        deal bool default false
+);
+```
+
+有一个业务系统会实时的将已经成交（deal 字段为 true）的订单数据转储，现在我们仅需要一个清理 程序，将已经成 交的数据从 orders 表删除并记录被删除的数据id。下面哪个操作是对的？
+
+## 答案
+
+在一个独立的定时任务中执行
+
+```mysql
+delete
+from orders
+where deal;
+```
+
+## 选项
+
+### A
+
+在一个独立的定时任务中执行
+
+```mysql
+truncate orders;
+```
+
+### B
+
+在一个独立的定时任务中执行
+
+```mysql
+delete
+from orders;
+```
+
+### C
+
+在一个独立的定时任务中执行
+
+```mysql
+drop table orders;
+create table if not exists orders (
+                        id int primary key auto_increment,
+                        item_id int,
+                        amount int,
+                        unit_price decimal(12, 4),
+                        total_price decimal(12, 4),
+                        description varchar(2000),
+                        ts timestamp default now(),
+                        deal bool default false
+);
+```
+
+### D
+
+建立视图
+
+```mysql
+create view order_view as
+select id, meta, content, created_at
+from orders
+where not deal;
+```
+
+并要求业务系统只能访问这个视图。
+
+### E
+
+在一个独立的定时任务中执行
+
+```mysql
+delete
+from orders
+where deal;
+```
+
+并记录操作前后表中的最大 id
\ No newline at end of file

data/1.MySQL初阶/6.数据查询/1.SELECT/config.json

 {
   "node_id": "mysql-f5527eae7f3148108c92ff99a6d4ed4a",
-  "keywords": [],
+  "keywords": ["查询", "select"],
   "children": [],
-  "export": [],
+  "export": [
+    "select.json"
+  ],
   "keywords_must": [],
   "keywords_forbid": [],
   "group": 0

data/1.MySQL初阶/6.数据查询/1.SELECT/select.json

+{
+  "type": "code_options",
+  "author": "ccat",
+  "source": "select.md",
+  "notebook_enable": false,
+  "exercise_id": "c873b09db60f4f93a8603a15e31d2a3a"
+}
\ No newline at end of file

data/1.MySQL初阶/6.数据查询/1.SELECT/select.md

+# 基本语法
+
+下列 SQL 语句，哪一项不合法？
+
+## 答案
+
+```mysql
+from test select abc;
+```
+
+## 选项
+
+
+### A
+
+```mysql
+select 3.14;
+```
+
+### B
+
+```mysql
+select * from employee;
+```
+
+### C
+
+```mysql
+select * from employee where dept = 'hr';
+```
+
+### D
+
+```mysql
+select id, name, dept, salary from employee where salary > 10000;
+```
+
+### E
+
+```mysql
+select now();
+```
+

data/1.MySQL初阶/6.数据查询/2.WHERE/config.json

@@ -2,7 +2,9 @@
   "node_id": "mysql-91cc9c73e58945d3ba654370a057a1c7",
   "keywords": [],
   "children": [],
-  "export": [],
+  "export": [
+    "where.json"
+  ],
   "keywords_must": [],
   "keywords_forbid": [],
   "group": 0

data/1.MySQL初阶/6.数据查询/2.WHERE/where.json

+{
+  "type": "code_options",
+  "author": "ccat",
+  "source": "where.md",
+  "notebook_enable": false,
+  "exercise_id": "1407e367ecca4e159cb7777fe141e8d4"
+}
\ No newline at end of file

data/1.MySQL初阶/6.数据查询/2.WHERE/where.md

+# Where 条件
+
+Joe 希望从 orders 表
+
+```mysql
+create table orders
+(
+    id          int primary key auto_increment,
+    item_id     int,
+    amount      int,
+    unit_price  decimal(12, 4),
+    total_price decimal(12, 4),
+    description varchar(2000),
+    ts          timestamp default now(),
+    deal        bool      default false
+);
+```
+
+查询 2022 年 5 月 25 日下单的所有单价低于 20 的订单id，那么这个查询应该如何写？
+
+## 答案
+
+```mysql
+select id
+from orders
+where date(ts) = '2022-05-25'
+  and unit_prise < 20;
+```
+
+## 选项
+
+### A
+
+```mysql
+select id
+from (select * from orders where date(ts) = '2022-05-25') as o
+where unit_prise < 20;
+```
+
+### B
+
+```mysql
+select id
+from orders
+where date(ts) = '2022-05-25'
+   or unit_prise < 20;
+```
+
+### C
+
+```mysql
+select id
+from orders 
+if date(ts) = '2022-05-25' or unit_prise < 20;
+```
+
+### D
+
+```mysql
+select id
+from orders
+which date(ts) = '2022-05-25'
+   or unit_prise < 20;
+```

data/1.MySQL初阶/6.数据查询/3.运算符/config.json

 {
   "node_id": "mysql-8f2aac71ea494f1b84372d43aa436135",
-  "keywords": [],
+  "keywords": [
+    "operator",
+    "运算符"
+  ],
   "children": [],
-  "export": [],
+  "export": [
+    "geo.json"
+  ],
   "keywords_must": [],
   "keywords_forbid": [],
   "group": 0

data/1.MySQL初阶/6.数据查询/3.运算符/geo.json

+{
+  "type": "code_options",
+  "author": "ccat",
+  "source": "geo.md",
+  "notebook_enable": false,
+  "exercise_id": "09df5b5537d340fab861362b9123fbfd"
+}
\ No newline at end of file

data/1.MySQL初阶/6.数据查询/3.运算符/geo.md

+# 数值计算
+
+Points 表结构如下：
+
+```mysql
+create table points(
+    id int primary key auto_increment,
+    x float,
+    y float
+)
+```
+
+现在 Joe 想要求写一个查询，得到每个点的id和模。即 √(x^2+y^2) 。这个查询应该是：
+
+## 答案
+
+```mysql
+select id, sqrt(x^2 + y^2) from points;
+```
+
+## 选项
+
+### A
+
+```mysql
+select sqrt(vx+vy) from (select x^2 as vx, y^2 as vy from points) as t;
+```
+
+### B
+
+```mysql
+select sqrt(vx + vy) from points where x^2 as vx, y^2 as vy ;
+```
+
+### C
+
+```mysql
+select id + sqrt(x^2 + y^2) from points;
+```
+
+### D
+
+```mysql
+select id || sqrt(x^2 + y^2) from points;
+```
\ No newline at end of file

gears/sql/goods.sql

+create table goods(
+    id int primary key auto_increment,
+    category_id int,
+    category varchar(64),
+    name varchar(256),
+    price decimal(12, 4),
+    stock int,
+    upper_time timestamp
+)
\ No newline at end of file

gears/sql/orders.sql

+create table orders (
+                        id int primary key auto_increment,
+                        item_id int,
+                        amount int,
+                        unit_price decimal(12, 4),
+                        total_price decimal(12, 4),
+                        description varchar(2000),
+                        ts timestamp default now(),
+                        deal bool default false
+);
\ No newline at end of file

gears/sql/points.sql

+create table points(
+    id int primary key auto_increment,
+    x float,
+    y float
+)
\ No newline at end of file