生成一个简单的出入库系统的代码

以下是一个使用 Python 实现的简单出入库系统代码，仅供参考：

import sqlite3

# 连接数据库
conn = sqlite3.connect('inventory.db')
c = conn.cursor()

# 创建库存表和出入库记录表
c.execute('''CREATE TABLE IF NOT EXISTS inventory
             (id INTEGER PRIMARY KEY AUTOINCREMENT,
              name TEXT NOT NULL,
              quantity INTEGER NOT NULL,
              unit TEXT NOT NULL)''')

c.execute('''CREATE TABLE IF NOT EXISTS inventory_log
             (id INTEGER PRIMARY KEY AUTOINCREMENT,
              name TEXT NOT NULL,
              quantity INTEGER NOT NULL,
              type TEXT NOT NULL,
              created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP)''')

# 出库函数
def out(name, quantity):
    # 查询库存数量
    c.execute("SELECT quantity FROM inventory WHERE name=?", (name,))
    result = c.fetchone()
    if result is None:
        print('物品不存在')
        return
    else:
        current_quantity = result[0]
        if current_quantity < quantity:
            print('库存不足')
            return
        else:
            # 更新库存数量
            c.execute("UPDATE inventory SET quantity=? WHERE name=?", (current_quantity - quantity, name))
            conn.commit()
            # 添加出库记录
            c.execute("INSERT INTO inventory_log (name, quantity, type) VALUES (?, ?, ?)", (name, quantity, '出库'))
            conn.commit()
            print('出库成功')

# 入库函数
def in_(name, quantity):
    # 查询库存数量
    c.execute("SELECT quantity FROM inventory WHERE name=?", (name,))
    result = c.fetchone()
    if result is None:
        # 添加新物品
        c.execute("INSERT INTO inventory (name, quantity, unit) VALUES (?, ?, ?)", (name, quantity, '个'))
        conn.commit()
    else:
        # 更新库存数量
        current_quantity = result[0]
        c.execute("UPDATE inventory SET quantity=? WHERE name=?", (current_quantity + quantity, name))
        conn.commit()
    # 添加入库记录
    c.execute("INSERT INTO inventory_log (name, quantity, type) VALUES (?, ?, ?)", (name, quantity, '入库'))
    conn.commit()
    print('入库成功')

# 查询库存记录函数
def show_inventory():
    c.execute("SELECT * FROM inventory")
    result = c.fetchall()
    if result:
        for row in result:
            print(row[0], row[1], row[2], row[3])
    else:
        print('库存为空')

# 查询历史库存信息函数
def show_history(name):
    c.execute("SELECT * FROM inventory_log WHERE name=?", (name,))
    result = c.fetchall()
    if result:
        for row in result:
            print(row[0], row[1], row[2], row[3], row[4])
    else:
        print('该物品没有历史记录')

# 菜单函数
def menu():
    while True:
        print('请选择操作：')
        print('1. 出库')
        print('2. 入库')
        print('3. 查询库存记录')
        print('4. 查询历史库存信息')
        print('0. 退出')
        choice = input()
        if choice == '1':
            name = input('请输入物品名称：')
            quantity = int(input('请输入出库数量：'))
            out(name, quantity)
        elif choice == '2':
            name = input('请输入物品名称：')
            quantity = int(input('请输入入库数量：'))
            in_(name, quantity)
        elif choice == '3':
            show_inventory()
        elif choice == '4':
            name = input('请输入物品名称：')
            show_history(name)
        elif choice == '0':
            break
        else:
            print('无效操作')

# 运行菜单函数
menu()

# 关闭数据库连接
conn.close()

这个代码实现了出库、入库、查询库存记录和查询历史库存信息等操作，使用 SQLite3 作为数据库。在实际应用中，还需要根据需求进行修改和完善。