如何实现“mysql 查询删除数据记录”

一、流程表格

步骤 描述
1 连接到 MySQL 数据库
2 构建 SQL 查询语句
3 执行 SQL 查询语句
4 查看查询结果
5 构建 SQL 删除语句
6 执行 SQL 删除语句
7 确认删除结果

二、具体步骤及代码示例

1. 连接到 MySQL 数据库

```python
import mysql.connector

# 创建数据库连接
mydb = mysql.connector.connect(
  host="localhost",
  user="root",
  password="password",
  database="mydatabase"
)

# 创建游标对象
mycursor = mydb.cursor()


### 2. 构建 SQL 查询语句

```markdown
```python
# 构建 SQL 查询语句
sql = "SELECT * FROM customers WHERE address = 'Park Lane 38'"


### 3. 执行 SQL 查询语句

```markdown
```python
# 执行 SQL 查询语句
mycursor.execute(sql)


### 4. 查看查询结果

```markdown
```python
# 获取查询结果
myresult = mycursor.fetchall()

# 输出查询结果
for x in myresult:
  print(x)


### 5. 构建 SQL 删除语句

```markdown
```python
# 构建 SQL 删除语句
sql = "DELETE FROM customers WHERE address = 'Park Lane 38'"


### 6. 执行 SQL 删除语句

```markdown
```python
# 执行 SQL 删除语句
mycursor.execute(sql)


### 7. 确认删除结果

```markdown
```python
# 确认删除结果
print(mycursor.rowcount, " 条记录已删除")


## 三、类图示例

```mermaid
classDiagram
    class Developer {
        - name: String
        - experience: String
        + teachBeginner(): void
    }
    class Beginner {
        - name: String
    }

    Developer <|-- Beginner

四、序列图示例

sequenceDiagram
    participant Developer
    participant Beginner

    Developer->Beginner: teachBeginner()
    Beginner->Developer: askQuestion()
    Developer->Developer: Connect to MySQL database
    Developer->Developer: Build SQL query statement
    Developer->Developer: Execute SQL query statement
    Developer->Developer: View query result
    Developer->Developer: Build SQL delete statement
    Developer->Developer: Execute SQL delete statement
    Developer->Developer: Confirm delete result

结尾

通过以上步骤，你已经学会了如何在 MySQL 中查询和删除数据记录。希望本文对你有所帮助，如果有任何疑问，欢迎向我提问。祝你在开发的道路上越走越远！