Using Python to Operate Apache Cassandra

To operate the Apache Cassandra database in Python, you need to use a Python driver called the Cassandra driver, which provides the ability to interact with the Cassandra database. The most commonly used Cassandra drivers are the Python Cassandra driver (Python Cassandra Driver or simply PyCassandra) and the DataStax Python driver (DataStax Python Driver or simply DataStax Driver). This article will demonstrate how to use the DataStax Python driver. Installation dependencies Firstly, you need to install the DataStax Python driver, which can be installed using the pip command: python pip install cassandra-driver Connect to Cassandra database The following code snippet demonstrates how to connect to the Cassandra database: python from cassandra.cluster import Cluster #Establishing cluster connections Cluster=Cluster (['IP Address']) session = cluster.connect() #Keyspace to access Keyspace='Keyspace name' #Connect to Keyspace session.set_keyspace(keyspace) Among them, ['IP address'] should be replaced with the IP address of one or more nodes in the Cassandra cluster, and 'keyspace name' should be replaced with the keyspace name to be accessed. insert data The following code snippet demonstrates how to insert data into the Cassandra database: python from cassandra.query import SimpleStatement #Prepare to insert statement Insert_ Statement=session. prepare ("Insert INTO keyspace based table name (column name 1, column name 2) VALUES (?,?)") #Execute insert statement Session. execute (insert_statement, ('Value 1 ','Value 2') Among them, 'keyspace based table name' should be replaced with the table name where the data is to be inserted, 'column name 1' and 'column name 2' should be replaced with the column names in the table, and 'value 1' and 'value 2' should be replaced with the actual values to be inserted. Query data The following code snippet demonstrates how to query data from the Cassandra database: python from cassandra.query import SimpleStatement #Prepare query statements Select_ Statement=session. prepare ("SELECT * From keyspace based table name WHERE column name 1=?") #Execute query statements Result_ Set=session. execute (select_statement, ('value 1 ',)) #Print query results for row in result_set: print(row) Among them, 'keyspace based table name' should be replaced with the table name of the data to be queried, 'column name 1' should be replaced with the column name to be queried, and 'value 1' should be replaced with the condition value of the query. Update data The following code snippet demonstrates how to update data in the Cassandra database: python from cassandra.query import SimpleStatement #Preparing to update statements Update_ Statement=session. prepare ("UPDATE keyspace based table name SET column name 1=? WHERE column name 2=?") #Execute update statement Session. execute (update_statement, ('new value ',' conditional value ') Among them, 'keyspace based table name' should be replaced with the table name of the data to be updated, 'column name 1' should be replaced with the column name to be updated, 'new value' should be replaced with the new value to be updated, 'column name 2' should be replaced with the conditional column name of the updated data, and 'conditional value' should be replaced with the conditional value of the updated data. Delete data The following code snippet demonstrates how to delete data from the Cassandra database: python from cassandra.query import SimpleStatement #Prepare to delete statement Delete_ Statement=session. prepare ("DELETE FROM keyspace based table name WHERE column name=?") #Execute delete statement Session. execute (delete_statement, ('conditional value ',)) Among them, 'keyspace based table name' should be replaced with the table name of the data to be deleted, 'column name' should be replaced with the column name of the data to be deleted, and 'condition value' should be replaced with the condition value of the data to be deleted. I hope these sample codes can help you start using Python to operate the Apache Cassandra database. Please note that these are just some basic examples, Cassandra's functionality is very powerful, and there are more advanced uses to explore.