Informix database management system technical principle

Informix database management system technical principle introduction: Informix database management system (DBMS) is a relationship database management system that has high performance, reliability, and scalability, which can meet various data management needs.This article will introduce the technical principles of Informix DBMS, including database architecture, data storage and query optimization. 1. Database architecture: Informix DBMS uses a multi -layer database architecture, including database server layers, storage management and application interface layers.The database server layer is responsible for handling user requests, storing the management of the physical storage and access to the management data, and the application interface layer provides an interface that interacts with the application.This layered architecture can improve the maintenance and scalability of the system. 2. Data storage: Informix DBMS supports a variety of storage models, including relations, object -oriented, and object -related databases.It uses data structures similar to B+trees to organize data to improve query performance.Data is stored in the table space, and each table space contains one or more data files.Table spaces can manage different data objects, such as tables, indexes and storage procedures. 3. Query optimization: Informix DBMS uses a variety of query optimization techniques to improve query performance.This includes query rewrite, query optimizer and execution plan generation.The query rewrite can transform complex queries into simpler equivalent queries to reduce the execution time of the query.Query optimizers use statistical information and inspiration algorithms to select the best query execution plan.The execution plan generates the execution plan based on the selection of the query optimizer, including the access order of the table, the connection operation and the use of the index. 4. Complete programming code and configuration: The following is a sample program that uses the Informix database management system to show the process of how to connect to the database, insert data, and query data. import informixdb # 连 to the database conn = informixdb.connect(database="mydb", user="myuser", password="mypassword") # 创 创 cursor = conn.cursor() # Insert data cursor.execute("INSERT INTO mytable (name, age) VALUES (?, ?)", ("John", 25)) # Submit transaction conn.commit() # Query data cursor.execute("SELECT name, age FROM mytable") result = cursor.fetchall() for row in result: print(f"Name: {row[0]}, Age: {row[1]}") # Close the cursor and connection cursor.close() conn.close() Please note that the configuration information such as databases, users and passwords in the above code should be modified according to the actual situation. in conclusion: Informix database management system is a powerful and flexible DBMS, which has advanced technical principles and rich functions.By understanding Informix DBMS's database architecture, data storage and query optimization, we can better understand its working principles and can write high -efficiency and reliable database applications.