Cred Interview Question | Improve Performance
Question
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Answers ( 2 )
1) Avoid unnecessary joins
2) Create indexes
3) Avoid * in SELECT statement if all columns are not required.
4) Choose appropriate DataTypes for storing data.
5) Avoid cursors as cursors are slow in performance.
1. Use indexes efficiently
2. Create all primary and foreign keys and relationships among tables.
3. Avoid using Select*, rather mention the needed columns and narrow the resultset as needed.
4. Reduce joins and heavy clauses like GROUP BY if not needed
5. Implement queries as stored procedures.
6. Use data types wisely
7. Instead of NULLS use string values such as N/A