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Python程式設計:使用sqlalchemy對資料庫進行增删改查1、插入資料2、删除資料3、修改資料4、查詢資料

文檔: https://docs.sqlalchemy.org/en/13/core/engines.html 連結字元串

# default
engine = create_engine('mysql://scott:tiger@localhost/foo')

# mysqlclient (a maintained fork of MySQL-Python)
engine = create_engine('mysql+mysqldb://scott:tiger@localhost/foo')

# PyMySQL
engine = create_engine('mysql+pymysql://scott:tiger@localhost/foo')      

管理資料庫連接配接

# -*- coding: utf-8 -*-

from sqlalchemy import create_engine, text

db_url = "mysql://root:[email protected]:3306/demo"

engine = create_engine(db_url, echo=True)

db = engine.connect()

db.close()      

備注:echo 參數可以開啟SQL語句日志列印

1、插入資料

insert = "insert into student(name)values(:name)"

# 插入資料 單條
dct = {"name": "Tom"}

result = db.execute(text(insert), dct)
print(result.rowcount)  # 1

# 插入資料 多條
# 注意:
# peewee的特殊字元: %
# pymysql的特殊字元: ?
# 都能正常寫入,不需要特殊轉義

data = [
    {"name": "Tom"},
    {"name": "Tom?"},
    {"name": "Tom%"}
]

result = db.execute(text(insert), data)
print(result.rowcount) # 3      

2、删除資料

delete = "delete from student where id=1"
result = db.execute(text(delete))
print(result.rowcount) # 1      

3、修改資料

update = "update student set sex='2' where id=1"
result = db.execute(text(update))
print(result.rowcount)  # 1      

4、查詢資料

select = "select id, name from student where id=1"
result = db.execute(text(select))
print(result.keys())  # ['id', 'name']
print(result.fetchall())  # [(50, 'Tom')]
print(result.rowcount)  # 1

for row in cursor:
   print(row["name"])