Python如何在每次插入新数据时自动生成不存在的主键

CREATE TABLE example (
    id INTEGER PRIMARY KEY AUTOINCREMENT,
    name TEXT NOT NULL
);

import sqlite3

conn = sqlite3.connect('example.db')
c = conn.cursor()

# 插入数据
c.execute("INSERT INTO example (name) VALUES (?)", ('Alice',))
conn.commit()

# 获取最后插入的ID
last_row_id = c.lastrowid
print(f"Last inserted ID: {last_row_id}")

conn.close()

CREATE TABLE example (
    id INT AUTO_INCREMENT PRIMARY KEY,
    name VARCHAR(255) NOT NULL
);

import mysql.connector

mydb = mysql.connector.connect(
  host="localhost",
  user="yourusername",
  password="yourpassword",
  database="yourdatabase"
)

mycursor = mydb.cursor()

# 插入数据
sql = "INSERT INTO example (name) VALUES (%s)"
val = ("Bob",)
mycursor.execute(sql, val)
mydb.commit()

# 获取最后插入的ID
last_row_id = mycursor.lastrowid
print(f"Last inserted ID: {last_row_id}")

CREATE TABLE example (
    id SERIAL PRIMARY KEY,
    name VARCHAR(255) NOT NULL
);

import psycopg2

conn = psycopg2.connect(
    dbname="yourdatabase",
    user="yourusername",
    password="yourpassword",
    host="localhost"
)

cur = conn.cursor()

# 插入数据
cur.execute("INSERT INTO example (name) VALUES (%s)", ('Charlie',))
conn.commit()

# 获取最后插入的ID
last_row_id = cur.fetchone()[0]
print(f"Last inserted ID: {last_row_id}")

conn.close()