That is, it is fine if the process crashes and all the data is lost. I don’t need the durability guarantee.The machine I am using is MacBook Pro, 2019 (2.4 GHz Quad Core i5, 8GB, 256GB SSD, Big Sur 11.1)Īspects I was willing to compromise on were: The area column would hold six digits area code (any six digits would do, no validation). Understanding the impact of using AUTOINCREMENT helps in designing databases that ensure data consistency and integrity.The generated data would be random with following constraints: SQLite's lastrowid attribute is incredibly useful for getting the ID of the last inserted row, particularly when you need to reference the new record immediately. ![]() This approach ensures data integrity and is crucial for maintaining unique identifiers throughout the database's lifespan. My_conn.execute('''CREATE TABLE IF NOT EXISTS student(id integer primary key AUTOINCREMENT, If this record is deleted and a new one is added, the new ROWID without AUTOINCREMENT would be 5. Let's consider a case where the highest ROWID is 5. However, with AUTOINCREMENT, SQLite ensures the ID is always one higher than the highest ID ever used, guaranteeing uniqueness. Without AUTOINCREMENT, SQLite assigns the next highest available ID. SQLite's AUTOINCREMENT keyword ensures each new record receives a unique ID that has never been used, even if previous records are deleted. This snippet will insert a new student record and print the ID assigned to it by SQLite. My_query = "INSERT INTO student(name,class,mark,gender) \ Inserting Data and Retrieving the Last Row IDĪfter inserting a new record, we can retrieve the unique ID assigned to it using lastrowid. My_conn.execute('''CREATE TABLE IF NOT EXISTS student(id integer primary key, ![]() The id column is set as an integer primary key. We'll define columns for id, name, class, mark, and gender. Let's see how this works with an example of a student database.įirst, let's create a student table. SQLite's lastrowid feature makes this task straightforward. When working with SQLite databases, it's often necessary to get the unique ID of the last inserted record. Output ( as we already added the records with the above IDs )Įrror: UNIQUE constraint failed: student.id Understanding SQLite's lastrowidĪUTOINCREMENT and INTEGER Primary Key column of SQLite database table Number of records added by using rowcount my_data=[(18, 'Big John', 'Four', 55, 'female'),Ĭurs=my_conn.executemany(my_query,my_data)īy using try except we can print the error message if any and that will help in debugging the script. We can check the row id of the last inserted records by using last_insert_rowid(). More records can be added by using executemany() function. ![]() Print(id) # 3 Adding multiple records / rows X=my_conn.execute('''select last_insert_rowid()''') We can check the ROWID of this added record. My_query="INSERT INTO student values(?,?,?,?,?)" We have used placeholders ( ? ) in our query and note that my_data is a tuple used for passing value to execute() method for our query. This is required to prevent injection attack. Use ? as placeholder and a provide a tuple to pass the value to query or execute() method. Always use parameterized query when the data is coming from unknown sources.
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