When Is Using `SELECT *` in SQL Queries Justified?

Selecting the Optimal: Exploring the Justification for SELECT * Usage

In the realm of database programming, the concept of selecting all columns using SELECT has been a subject of debate for its potential drawbacks. While conventional wisdom often advises against this practice, under certain specific circumstances, SELECT can be a viable option.

When SELECT * Stands Its Ground

Despite its reputation as a potential liability, SELECT * can be justified in certain scenarios:

• Audit Triggers: When creating audit triggers, using SELECT * ensures that any changes to the base table's columns will be reflected in the audit record, preventing potential omissions in audit data.
• Derived Tables and Column Table Expressions: In derived tables and column table expressions, using SELECT * can simplify code by referencing all columns present in the query without explicitly listing them. This approach can be efficient when dealing with complex queries or when the column list is likely to change.
• Views (Cautiously): While not generally recommended, SELECT can be used in views when considering specific database characteristics. For instance, in SQL Server, using SELECT in the underlying table expression of a view can prevent issues with outdated column metadata. However, it's crucial to regularly refresh the view using sp_refreshview to ensure accurate metadata.

Conclusion

While SELECT should generally be avoided in production code to prevent wasted resources or incorrect data, it can be justified in specific use cases such as audit triggers, derived tables, and views under certain circumstances. By carefully considering these exceptions, programmers can harness the power of SELECT when appropriate and optimize their database queries accordingly.

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