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Fiverr Pro
English
$
USD
I will write, fix, debug, and optimize your sql queries
About this Gig
Is your SQL query failing, returning incorrect results, or running slowly? I will diagnose the problem, provide clean corrected SQL, and clearly explain what changed.
I work with MySQL, PostgreSQL, SQL Server, and SQLite.
I can help with:
- Writing SELECT and reporting queries
- Syntax errors and incorrect results
- JOINs, filters, aggregations, subqueries, CTEs, and window functions
- Query readability and performance improvements
Every package includes clean SQL, an explanation, and test notes based on your schema and sample data.
Standard and Premium include optimization and index advice where relevant. Premium adds execution-plan review and a detailed report. Performance gains depend on your data and database setup.
This gig covers SELECT/reporting queries. One query means one SQL statement, including its CTEs. Stored procedures, migrations, scheduling, and production deployment are excluded.
Send your database version, query, expected result, schema, and sanitized sample data. For performance work, include indexes and execution plans. Never send me the credentials.
Message me before ordering complex queries so I can confirm the scope and package.
Database type:
Centralized database
•
Relational database
Platform:
MySQL
•
PostgreSQL
•
SQLite
•
SQL Server
Expertise:
SQL
•
DQL
•
Performance
•
Query optimization
FAQ
Which databases do you support?
I support MySQL, PostgreSQL, SQL Server, and SQLite. Please share your database engine and version so I can use the correct SQL syntax. For other platforms, message me before ordering.
What information do you need to get started?
Please provide your query, the exact error or incorrect result, your expected output, relevant table definitions, and sanitized sample data. For performance work, also include existing indexes, approximate table sizes, and execution plans. Please remove passwords, credentials, and personal info
What counts as one query?
One query means one executable SELECT statement for one requested output. Its subqueries and CTEs count as part of that statement. Multiple statements count separately. Please message me before ordering unusually long or complex queries so I can confirm the scope.
Can you improve a slow SQL query?
Standard and Premium include query optimization and index advice where relevant. Premium also includes execution-plan review and a detailed report. Improvements depend on your data, indexes, hardware, and database configuration, so I cannot guarantee a specific speed increase.
Do you need access to my database?
No. I work from the query, table definitions, and sanitized sample data you provide. Production database access is outside this gig. If you cannot provide representative sample data, message me first: I can review the SQL, but testing and verification will be limited.
What will I receive?
Every package includes a SQL file, a clear explanation of the changes, and test notes describing what was checked and any assumptions or limitations. Standard adds optimization and index advice where relevant. Premium adds execution-plan findings and a detailed report.
What does a revision include?
A revision covers adjustments to the delivered query against your original requirements. New outputs, additional queries, changed business rules, or an expanded scope require an additional order or custom offer. Basic and Standard include one revision; Premium includes two.
What is outside the scope of this gig?
This gig covers SELECT and reporting queries. It does not include data-changing statements such as INSERT, UPDATE, or DELETE; stored procedures; triggers; database design; migrations; scheduling; administration; or production deployment.
