SQL injection is a common web hacking technique that can destroy databases. Malicious code is placed in SQL statements via web page input. Users enter SQL instead of their actual values
INSERT creates new rows in a table. Can insert rows from values or queries. Column names can be listed in any order. Default values are used for missing columns. Automatic type conversion is attempted
UPDATE modifies values in rows satisfying specified conditions. Only modified columns need explicit specification in SET clause. Can modify tables using sub-selects or FROM clause. Optional RETURNING clause computes values based on updated rows
Sample databases help build solutions portfolio and learn new technologies. They provide training environment for SQL queries and features. Useful for testing backup solutions before production deployment
WHERE clause filters datasets based on specified criteria. Multiple filters can be combined using AND operator. WHERE clause must come before GROUP BY in queries
Data science remains resilient despite tech industry layoffs. Only 10% of tech layoffs affected data science positions. Data science skills crucial for business success