Troubleshooting Python MySQL Insert Operations

In Python, using the MySQL API to interact with a MySQL database, inserting records can encounter obstacles. This article addresses one such issue where records fail to be inserted despite seemingly correct implementation.

The provided code establishes a connection to the database and attempts to insert a record into the 'documents' table. However, the insert operation fails. To resolve this issue, it's crucial to understand the importance of database transactions.

In MySQL, changes to the database are managed through transactions. A transaction begins when a connection is established and ends when the connection is closed or when a commit or rollback operation is explicitly called. Any changes made to the database during a transaction are not permanent until the transaction is committed.

In the provided code, the insert operation is executed successfully, but the changes are not committed to the database before the connection is closed (using db.close()). Without committing the transaction, the insert operation is discarded once the connection is closed.

To resolve this issue and ensure the insert operation is successful, you should include a call to db.commit() before closing the database connection. This action commits the transaction, making the inserted record persistent in the database.

Here's the modified code that includes the commit operation:

db = MySQLdb.connect("localhost", "root", "padmaramulu", "pdfsearch")
cursor = db.cursor()
# cursor.execute("""CREATE TABLE IF NOT EXISTS documents (docid INT NOT NULL ,PRIMARY KEY(docid),docname CHAR(30)) engine=innodb""")
temp = "hello"; number = 2;
cursor.execute('insert into documents(docid,docname) values("%d","%s")' % (number, temp))
db.commit()
db.close()

By including the db.commit() call, the changes made during the transaction, including the insert operation, are committed to the database and become permanent.