Additional Notes
Why might you avoid using indexes on columns with unique values?
Track: Java
Topic: SQL for Java Devs
Focus: Indexes
Java: Indexes
Answer
Indexes offer little benefit on unique-value columns.
If a column's values are unique, like a primary key, each query essentially needs the same effort as scanning the table. Indexes are less useful here and may unnecessarily slow down writes. For instance, indexing a 'UUID' primary key in a 'sessions' table might not justify the write overhead.
If a column's values are unique, like a primary key, each query essentially needs the same effort as scanning the table. Indexes are less useful here and may unnecessarily slow down writes. For instance, indexing a 'UUID' primary key in a 'sessions' table might not justify the write overhead.
Topics: Indexes Java SQL for Java Devs