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py-mo-sqlite3 #38

Open jzztf opened 6 years ago

jzztf commented 6 years ago

sqlite3 数据库

import sqlite3

# 建立连接
conn = sqlite3.connect('grade_1.db')

# 创建游标对象
c = conn.cursor()

# 为数据库添加表
c.execute("CREATE TABLE IF NOT EXITSTS class_1 VALUES(id INTEGER,name TEXT,math REAL,Chinese REAL,English REAL) ")
# INTEGER ==> int; TEXT ==> str; REAL ==> float; BLOB ==> bytes; NULL ==> None

# 为表添加数据
c.execute("INSERT INTO class_1 VALUES(1,'张三',80,90,88)")
# 提交
conn.commit()

# 为表添加多行数据(引用Python变量,使用"?"而不是"%s")
c.execute("INSERT INTO class_1 VALUES(?,?,?,?,?)",(id,name,math,Chinese,English))
# 提交
conn.commit()

# 查看数据
c.execute("SELECT * FROM class_1 WHERE math> 90 ORDER BY id)
# c,fetchone() 只取一行
for row in c.fetchall():
    print(row)

# 更新数据库
c.execute("UPDATE class_1 SET math=88 WHERE name='zhangsan')
conn.commit()

# 删除行
c.execute("DELETE class_1 WHERE id=0)
conn.commit()

# 关闭数据库
c.close()
conn.close()