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I will fix and optimize complex sql queries and databases
Database Administrator, SQL and Software Engineer
I am a Software Engineer and Database Administrator with 5 years of professional experience in software development, database administration, SQL development, and data management.
I specialize in desi...
About this Gig
Do you have a complex, slow, or incorrect SQL query? I can help you fix, optimize, and improve your SQL queries and database performance.
I am a Software Engineer and Database Administrator with 5 years of professional experience in database management, SQL development, and software engineering.
I can help you with:
- Complex SQL queries
- SQL query optimization
- Database troubleshooting
- MySQL, PostgreSQL, SQL Server and Oracle
- Joins, subqueries, CTEs and aggregations
- Views and stored procedures
- Database performance analysis
- Data validation and consistency checks
- SQL errors and query debugging
I focus on clean, efficient, reliable, and maintainable SQL solutions adapted to your database structure and requirements.
Please contact me before placing an order for all types of projects.
Database type:
Relational database
Platform:
MS SQL
•
Oracle
•
PostgreSQL
•
SQLite
•
SQL Server
Expertise:
Data structure
•
Design
•
SQL
My Portfolio
FAQ
Can you help me fix a syntax error in my SQL query?
Yes. Send me your query and error message. I’ll quickly identify the issue and provide a corrected, working version.
I need help writing a simple SELECT query with filters.
I can write clean SELECT statements with WHERE, ORDER BY, and basic joins to retrieve exactly the data you need.
My query runs but returns wrong results. Can you check it?
Of course. I’ll review your logic, test edge cases, and correct filtering, joins, or grouping to return accurate results.
I need help writing a query with multiple JOINs and aggregations.
I can write complex queries using INNER/LEFT/RIGHT joins, GROUP BY, HAVING, and aggregate functions (SUM, COUNT, AVG, etc.) to summarize your data.
Can you help me migrate data between two tables or databases?
Yes. I’ll write INSERT ... SELECT or generate scripts to safely transfer data, handle conflicts, and preserve relationships.
Can you redesign a poorly structured database?
Yes. I can normalize or denormalize schemas, define primary/foreign keys, set data types, and suggest indexing strategies for better performance and integrity.
Can you design a database from my business description?
Yes. Just describe your business rules, workflows, and reporting needs. I'll extract entities, relationships, and constraints to build a robust model.
What is included in your database design service?
I provide a complete conceptual, logical, and physical data model. This includes: 1. Conceptual Data Model – entities, associations, and cardinalities 2. Logical Data Model – tables, foreign keys, and normalized structure 3. Physical Data Model – final SQL scripts with data types, indexe
Which databases do you support?
I mainly work with MySQL, PostgreSQL, Microsoft SQL Server and Oracle.
