Compare SQL Queries, Scripts, and Table Definitions
Paste two versions of a SQL query or schema to see what changed. Use the comparison options when formatting, comments, or letter case make the differences harder to read, then review the highlighted lines before you use the updated SQL.
⚙️ Comparison Options
🔍 Interactive SQL Diff Viewer
Paste original and modified SQL, then click Compare SQL to visualize differences
What is SQL Compare?
SQL Compare is a specialized code comparison tool designed specifically for database developers, DBA teams, and data engineers. It performs line-by-line and structural comparisons between two SQL scripts, DDL table definitions, stored procedures, or database queries.
Unlike generic text diff tools, an intelligent SQL compare tool offers options to strip comments, ignore keyword capitalization differences, collapse extra whitespace, and bypass statement ordering mismatches. This allows developers to focus on actual structural and logic changes rather than superficial formatting edits.
By running completely inside your browser, SQL Compare ensures that your sensitive database schemas, query logic, and table definitions remain 100% private and never touch third-party servers.
Why Compare SQL Scripts & Database Schemas?
Verify schema parity between Development, Staging, and Production databases before deploying database migrations.
Review ALTER TABLE DDL statements, added columns, removed constraints, or modified data types prior to execution.
Inspect complex stored procedures, functions, and triggers to pinpoint exact business logic modifications.
Conduct fast code reviews on SQL pull requests by focusing exclusively on functional logic changes.
Filter out trivial whitespace, comment edits, or lower/upper case keyword changes to highlight meaningful diffs.
Safely compare proprietary database schemas and internal SQL queries without transmitting code to external servers.
Key SQL Compare Features
Built for database administrators, data engineers, and backend software developers.
Side-by-Side & Inline Views
Toggle between a dual-pane side-by-side comparison grid and a unified inline diff view with line numbers.
SQL Comment & Case Normalization
Automatically strip inline/block comments and normalize keyword capitalization for accurate comparisons.
Similarity Scoring & Change Metrics
Calculates an exact similarity score (%) alongside added, removed, and modified line counters.
Multi-Dialect Support
Compatible with ANSI SQL, MySQL, PostgreSQL, SQL Server, SQLite, Oracle SQL, MariaDB, and Snowflake.
Multi-Format Diff Export
Export SQL comparison summaries in Markdown (`.md`), HTML Report, JSON diff format, or copy to clipboard.
Zero Cloud Transfers
100% in-browser processing. Your database schemas and sensitive queries are never stored or transmitted.
Supported SQL Dialects & Statements
Compare table definitions, column additions, data type modifications, primary keys, and foreign keys.
Inspect stored procedure bodies, user-defined functions, and trigger routines for logic changes.
Compare complex query joins, CTE expressions, subqueries, and CREATE VIEW definitions.
Audit INSERT, UPDATE, and DELETE data migration scripts across environments.
Review SQL changes before you apply them
When two SQL scripts look almost identical, a small change to a column, condition, index, or migration statement can be easy to miss. Compare the earlier version with the revised one to locate changes, separate meaningful edits from formatting differences, and prepare a review before running the new script.
Place the original SQL on one side and the edited or proposed version on the other. Use the exact files you intend to review, not snippets copied from different revisions.
Choose the SQL dialect and whether comments, whitespace, or letter case should be ignored. For a strict review, keep options that might hide a difference you need to see.
Run the comparison, inspect the highlighted changes, and move between differences. Check the surrounding SQL so each change is understood in context.
Use the available report export or copy action to share the differences with a teammate or keep a record alongside a migration review.
What to look at first
- New or removed columns, tables, indexes, constraints, or statements.
- Changed conditions, joins, default values, or data types that could alter results.
- Differences hidden by formatting choices—do not ignore comments or case if they matter to your review process.
- Migration steps that may behave differently across environments or database versions.
A text comparison helps you find edits, but it does not execute the SQL, prove that a migration is safe, or confirm that two live database schemas are identical. Read the surrounding statements and test important changes in the appropriate environment before deployment.
Frequently Asked Questions
What is SQL Compare and how does it work?
SQL Compare compares two SQL scripts or database schemas line-by-line, computing similarity scores and highlighting additions, deletions, and modifications in side-by-side or inline diff views.
Which SQL dialects are supported?
ANSI SQL, MySQL, PostgreSQL, SQL Server, SQLite, Oracle SQL, MariaDB, IBM Db2, Snowflake SQL, and BigQuery SQL.
Can I ignore comments and formatting differences?
Yes. You can enable options to strip comments (-- or /* */), ignore keyword case, collapse extra whitespace, ignore blank lines, and strip semicolons before comparing.
Is my SQL code sent to any server for comparison?
No. All diff processing happens 100% locally in your web browser. Your code and database structures remain private.
What export formats are available for comparison reports?
You can export comparison reports in Markdown (.md), HTML Report, JSON diff format, or copy the diff summary to your clipboard.
Compare Your SQL Scripts Now
Paste your SQL scripts and pinpoint every schema change, query edit, and DDL modification in seconds — with complete privacy.