diff --git a/demo1.py b/demo1.py
index a4e9e8a..ace155b 100644
--- a/demo1.py
+++ b/demo1.py
@@ -1,9 +1,12 @@
 import pymysql
 
-db = pymysql.connect(host='localhost', user='root', password=None, port=3306)
+db = pymysql.connect(host='localhost', user='root', password='jojo123456', port=3306)
+# n.光标，游标，指针
 cursor = db.cursor()
+
 cursor.execute('SELECT VERSION()')
 data = cursor.fetchone()
 print('Database version:', data)
-cursor.execute("CREATE DATABASE spiders DEFAULT CHARACTER SET utf8mb4")
+
+cursor.execute("CREATE DATABASE spider DEFAULT CHARACTER SET utf8mb4")
 db.close()
diff --git a/demo2.py b/demo2.py
index 1ad8d52..6a9e647 100644
--- a/demo2.py
+++ b/demo2.py
@@ -1,6 +1,7 @@
 import pymysql
 
-db = pymysql.connect(host='localhost', user='root', password=None, port=3306, db='spiders')
+# 创建数据库后，在连接时需要额外指定一个参数db
+db = pymysql.connect(host='localhost', user='root', password='jojo123456', port=3306, db='spider')
 cursor = db.cursor()
 sql = 'CREATE TABLE IF NOT EXISTS students (id VARCHAR(255) NOT NULL, name VARCHAR(255) NOT NULL, age INT NOT NULL, PRIMARY KEY (id))'
 cursor.execute(sql)
diff --git a/demo3.py b/demo3.py
index 13559a4..fa8fb4f 100644
--- a/demo3.py
+++ b/demo3.py
@@ -6,7 +6,7 @@
 age = 20
 
 db = pymysql.connect(host='localhost', user='root',
-                     password=None, port=3306, db='spiders')
+                     password='jojo123456', port=3306, db='spider')
 cursor = db.cursor()
 sql = 'INSERT INTO students(id, name, age) values(%s, %s, %s)'
 try:
diff --git a/demo4.py b/demo4.py
index a948f65..9670ff2 100644
--- a/demo4.py
+++ b/demo4.py
@@ -1,18 +1,19 @@
 import pymysql
 
 data = {
-    'id': '20120001',
-    'name': 'Bob',
-    'age': 20
+    'id': '20120003',
+    'name': 'Jeery',
+    'age': 22
 }
 table = 'students'
 keys = ', '.join(data.keys())
 values = ', '.join(['%s'] * len(data))
 db = pymysql.connect(host='localhost', user='root',
-                     password=None, port=3306, db='spiders')
+                     password='jojo123456', port=3306, db='spider')
 cursor = db.cursor()
-sql = 'INSERT INTO {table}({keys}) VALUES ({values})'.format(
-    table=table, keys=keys, values=values)
+# sql = 'INSERT INTO {table}({keys}) VALUES ({values})'.format(
+#     table=table, keys=keys, values=values)
+sql = f'INSERT INTO {table}({keys}) VALUES ({values})'
 try:
     if cursor.execute(sql, tuple(data.values())):
         print('Successful')
diff --git a/demo5.py b/demo5.py
index d8465a9..c4e7ed0 100644
--- a/demo5.py
+++ b/demo5.py
@@ -3,18 +3,22 @@
 data = {
     'id': '20120001',
     'name': 'Bob',
-    'age': 21
+    'age': 22
 }
 
 table = 'students'
 keys = ', '.join(data.keys())
 values = ', '.join(['%s'] * len(data))
 db = pymysql.connect(host='localhost', user='root',
-                     password=None, port=3306, db='spiders')
+                     password='jojo123456', port=3306, db='spider')
 cursor = db.cursor()
-sql = 'INSERT INTO {table}({keys}) VALUES ({values}) ON DUPLICATE KEY UPDATE '.format(
-    table=table, keys=keys, values=values)
-update = ','.join(["{key} = %s".format(key=key) for key in data])
+
+# sql = 'INSERT INTO {table}({keys}) VALUES ({values}) ON DUPLICATE KEY UPDATE '.format(
+#     table=table, keys=keys, values=values)
+# update = ','.join(["{key} = %s".format(key=key) for key in data])
+# duplicate adj.完全一样的，复制的
+sql = f'INSERT INTO {table}({keys}) VALUES ({values}) ON DUPLICATE KEY UPDATE '
+update = ','.join([f'{key} = %s' for key in data])
 sql += update
 try:
     if cursor.execute(sql, tuple(data.values())*2):
diff --git a/demo6.py b/demo6.py
index 90ae202..187a852 100644
--- a/demo6.py
+++ b/demo6.py
@@ -1,15 +1,15 @@
 import pymysql
 
 table = 'students'
-condition = 'age > 20'
+condition = 'age > 21'
 
-db = pymysql.connect(host='localhost', user='root', password=None, port=3306, db='spiders')
+db = pymysql.connect(host='localhost', user='root', password='jojo123456', port=3306, db='spider')
 cursor = db.cursor()
-sql = 'DELETE FROM  {table} WHERE {condition}'.format(table=table, condition=condition)
+# sql = 'DELETE FROM {table} WHERE {condition}'.format(table=table, condition=condition)
+sql = f'DELETE FROM {table} WHERE {condition}'
 try:
     cursor.execute(sql)
     db.commit()
 except:
     db.rollback()
-
-db.close()
\ No newline at end of file
+db.close()
diff --git a/demo7.py b/demo7.py
index 1d3f588..37f7778 100644
--- a/demo7.py
+++ b/demo7.py
@@ -1,9 +1,8 @@
 import pymysql
 
-sql = 'SELECT * FROM students WHERE age >= 20'
-
-db = pymysql.connect(host='localhost', user='root', password=None, port=3306, db='spiders')
+db = pymysql.connect(host='localhost', user='root', password='jojo123456', port=3306, db='spider')
 cursor = db.cursor()
+sql = 'SELECT * FROM students WHERE age >= 20'
 try:
     cursor.execute(sql)
     print('Count:', cursor.rowcount)
@@ -16,7 +15,7 @@
         print(row)
 except:
     print('Error')
-    
+
 sql = 'SELECT * FROM students WHERE age >= 20'
 try:
     cursor.execute(sql)
@@ -26,4 +25,4 @@
         print('Row:', row)
         row = cursor.fetchone()
 except:
-    print('Error')
\ No newline at end of file
+    print('Error')