Question

插入id 1和2.删除id 2.插入新行，它获取id 2而不是3.如何更改？我不想重用主键。

import sqlite3, os

os.remove('mydatabase.db')
conn = sqlite3.connect("mydatabase.db") # or use :memory: to put it in RAM
cursor = conn.cursor()

# create a table
cursor.execute("CREATE TABLE if not exists albums (id INTEGER PRIMARY KEY NOT NULL, title text, artist text, release_date text, publisher text, media_type text)")
cursor.execute("CREATE TABLE if not exists anti (id INTEGER, title text, artist text, release_date text, publisher text, media_type text)")
conn.commit()

cursor.execute("INSERT INTO albums VALUES (null, 'Glow', 'Andy Hunter', '7/24/2012', 'Xplore Records', 'MP3')")
cursor.execute("INSERT INTO albums VALUES (null, 'second', 'artist', '7/24/2012', 'Xplore Records', 'MP3')")
conn.commit()

cursor.execute("SELECT * FROM albums")
print(cursor.fetchall())

cursor.execute("INSERT INTO anti SELECT * FROM albums WHERE title='second'")
cursor.execute("DELETE FROM albums WHERE title='second'")
cursor.execute("INSERT INTO albums VALUES (null, 'third', 'artist', '7/24/2012', 'Xplore Records', 'MP3')")
conn.commit()

cursor.execute("SELECT * FROM albums")
print(cursor.fetchall())
cursor.execute("SELECT * FROM anti")
print(cursor.fetchall())

Answer 1

来自https://www.sqlite.org/autoinc.html：

如果AUTOINCREMENT关键字出现在INTEGER PRIMARY KEY之后，则会更改自动ROWID分配算法，以防止在数据库的生命周期内重用ROWID。换句话说，AUTOINCREMENT的目的是防止从以前删除的行重用ROWID。

不要使用已删除的主键

1 个答案: