What methods can be used to improve the performance of SQL query execution?

To improve SQL query performance, the following approaches can be used:

• Creating and optimizing indexes on frequently used columns.
• Avoiding fetching unnecessary data (use only the required columns instead of SELECT *).
• Using parameterized queries for plan reuse.
• Optimizing JOINs and WHERE conditions to reduce the amount of data processed.
• Analyzing the execution plan (EXPLAIN) to identify bottlenecks.
• Caching results of frequently executed queries.

Example of a parameterized query in Python using the psycopg2 library:

cursor.execute("SELECT * FROM users WHERE age > %s", (30,))