0.1

example/mysql_conn.py

@@ -8,15 +8,40 @@
 2023/4/13 13:59   zart20      1.0         None
 '''
 
+# pymysql 链接示例
+
 import pymysql
 
-db = pymysql.connect(host="127.0.0.1", port=3306, user='root', password="123123", charset="utf8", database="student")
 
-cursor = db.cursor()
+# db = pymysql.connect(host="127.0.0.1", port=3306, user='root', password="123123", charset="utf8")    # 链接数据库管理系统
+db = pymysql.connect(host="127.0.0.1", port=3306, user='root', password="123123", charset="utf8", database="student")   # 链接数据库
+
+cursor = db.cursor()        # 实例化游标对象
 
-cursor.execute("show tables;")
+cursor.execute("show databases;")   # 显示所有数据库
+cursor.execute("use student;")      # 选择指定数据库
+cursor.execute("show tables;")      # 执行数据库查询
 
-data = cursor.fetchall()
+data = cursor.fetchall()    #   取出游标中所有内容
 print(data)
 
 cursor.close()
+
+c2 = db.cursor()
+# c2.execute("show databases;")
+c2.execute("show tables;")
+print(c2.fetchall())
+
+# db.close()      # 关闭数据库链接
+
+# c3 = db.cursor()
+# c3.execute("show databases;")
+# print(c3.fetchall())
+
+
+
+
+
+
+
+

example/mysql_conn2.py

@@ -0,0 +1,25 @@
+# -*- encoding: utf-8 -*-
+'''
+@File    :   mysql_conn2.py   
+@License :   (C)Copyright 2018-2022
+
+@Modify Time      @Author    @Version    @Desciption
+------------      -------    --------    -----------
+2023/4/16 18:13   zart20      1.0         None
+'''
+
+# mysql-connector-python 链接示例
+
+import mysql.connector
+
+db = mysql.connector.connect(host="127.0.0.1", port=3306, user='root', password="123123", charset="utf8", database="student")
+
+cursor = db.cursor()
+
+cursor.execute("show databases;")
+
+data = cursor.fetchall()
+
+print(data)
+
+cursor.close()

example/pymysql_CRDU_student.py

@@ -0,0 +1,95 @@
+# -*- encoding: utf-8 -*-
+'''
+@File    :   creat_student.py   
+@License :   (C)Copyright 2018-2022
+
+@Modify Time      @Author    @Version    @Desciption
+------------      -------    --------    -----------
+2023/4/16 18:51   zart20      1.0         None
+'''
+import pymysql
+
+def create_table(db:pymysql.connect):
+    """
+    创建表
+    :param db: 数据库链接对象
+    :return:
+    """
+    cursor = db.cursor()
+    cursor.execute("DROP TABLE IF EXISTS student;")
+    sql = """CREATE TABLE Student (
+                                ID CHAR(10) NOT NULL,
+                                Name VARCHAR(20),
+                                Grade INT 
+                                );"""
+    cursor.execute(sql)
+    cursor.close()
+
+
+def insert_table(db:pymysql.connect):
+    cursor = db.cursor()
+    sql = """INSERT INTO Student VALUES ('001', 'CZQ', 70),('002', 'LHQ', 80),('003', 'MQ', 90), 
+                ('004', 'WH', 80),  ('005', 'HP', 70),('006', 'YF', 66),('007', 'TEST', 100);"""
+    try:
+        cursor.execute(sql)
+        db.commit()
+        cursor.close()
+    except:
+        db.rollback()
+        cursor.close()
+
+
+def delete_db(db:pymysql.connect):
+    cursor = db.cursor()
+    sql = "DELETE FROM Student WHERE Grade = %d;"% 100
+    print(sql)
+    try:
+        cursor.execute(sql)
+        db.commit()
+        cursor.close()
+    except Exception as e:
+        print(e)
+        db.rollback()
+        cursor.close()
+
+
+def update_db(db:pymysql.connect):
+    cursor = db.cursor()
+    sql = "UPDATE Student SET Grade = Grade + 3 WHERE ID = '%s';" % '003'
+    print(sql)
+    try:
+        cursor.execute(sql)
+        db.commit()
+        cursor.close()
+    except Exception as e:
+        print(e)
+        db.rollback()
+        cursor.close()
+
+
+
+if __name__ == '__main__':
+    db = pymysql.connect(host="127.0.0.1", port=3306, user='root', password="123123", charset="utf8",
+                         database="student")  # 链接数据库
+
+    create_table(db)
+
+    insert_table(db)
+
+    delete_db(db)
+
+    update_db(db)
+
+    # 检查数据库的变化
+    cursor2 = db.cursor()
+    cursor2.execute("show tables;")  # 显示所有表
+    print(cursor2.fetchall())
+    cursor2.execute("DESCRIBE student;")  # 查看表结构
+    print(cursor2.fetchall())
+
+    cursor2.execute("SELECT * FROM student;")  # 查看student表所有记录
+    print(cursor2.fetchall())
+
+
+    cursor2.close()
+    db.close()  # 关闭链接