How to retrieve inserted id after inserting row in SQLite using Python?

Question

How to retrieve inserted id after inserting row in SQLite using Python? I have table like this:

id INT AUTOINCREMENT PRIMARY KEY,
username VARCHAR(50),
password VARCHAR(50)

I insert a new row with example data username="test" and password="test". How do I retrieve the generated id in a transaction safe way? This is for a website solution, where two people may be inserting data at the same time. I know I can get the last read row, but I don’t think that is transaction safe. Can somebody give me some advice?

Asked By: Jane

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Source

Answer 1

You could use cursor.lastrowid (see "Optional DB API Extensions"):

connection=sqlite3.connect(':memory:')
cursor=connection.cursor()
cursor.execute('''CREATE TABLE foo (id integer primary key autoincrement ,
                                    username varchar(50),
                                    password varchar(50))''')
cursor.execute('INSERT INTO foo (username,password) VALUES (?,?)',
               ('test','test'))
print(cursor.lastrowid)
# 1

If two people are inserting at the same time, as long as they are using different cursors, cursor.lastrowid will return the id for the last row that cursor inserted:

cursor.execute('INSERT INTO foo (username,password) VALUES (?,?)',
               ('blah','blah'))

cursor2=connection.cursor()
cursor2.execute('INSERT INTO foo (username,password) VALUES (?,?)',
               ('blah','blah'))

print(cursor2.lastrowid)        
# 3
print(cursor.lastrowid)
# 2

cursor.execute('INSERT INTO foo (id,username,password) VALUES (?,?,?)',
               (100,'blah','blah'))
print(cursor.lastrowid)
# 100

Note that lastrowid returns None when you insert more than one row at a time with executemany:

cursor.executemany('INSERT INTO foo (username,password) VALUES (?,?)',
               (('baz','bar'),('bing','bop')))
print(cursor.lastrowid)
# None

Answered By: unutbu

Answer 2

All credits to @Martijn Pieters in the comments:

You can use the function last_insert_rowid():

The last_insert_rowid() function returns the ROWID of the last row insert from the database connection which invoked the function. The last_insert_rowid() SQL function is a wrapper around the sqlite3_last_insert_rowid() C/C++ interface function.

SQLite 3.35‘s `RETURNING` clause:

CREATE TABLE users (
  id INTEGER PRIMARY KEY,
  first_name TEXT,
  last_name TEXT
);

INSERT INTO users (first_name, last_name)
VALUES ('Jane', 'Doe')
RETURNING id;

returns requested columns of the inserted row in INSERT, UPDATE and DELETE statements. Python usage:

cursor.execute('INSERT INTO users (first_name, last_name) VALUES (?,?)'
               ' RETURNING id',
               ('Jane', 'Doe'))
row = cursor.fetchone()
(inserted_id, ) = row if row else None

Answered By: Stefan van den Akker

How to retrieve inserted id after inserting row in SQLite using Python?

Question:

Answers:

SQLite 3.35‘s `RETURNING` clause:

How to retrieve inserted id after inserting row in SQLite using Python?

Question:

Answers:

SQLite 3.35‘s RETURNING clause:

SQLite 3.35‘s `RETURNING` clause: