Compare and diff two SQL scripts. Fast, secure, and completely free. All processing happens in your browser — no data is sent to any server.
SQL Compare is not a text diff tool — it parses two SQL queries or statements into their logical structure (clauses, conditions, joins) and highlights differences in that structure, rather than flagging every whitespace or formatting change as if it mattered. Two queries that are logically identical but formatted differently (different keyword casing, different line breaks, aliases in a different order) would create a noisy, misleading diff under a plain text comparison; a structural comparison instead answers the actual question: did the query's logic change, and if so, where.
Reviewing a pull request that touches a SQL query is genuinely difficult with a generic text diff, because reformatting alone — reindenting, recapitalizing keywords, reordering aliases — creates a large, noisy diff that obscures the one WHERE condition or JOIN that actually changed. A structural comparison strips out the formatting noise so a reviewer can see, at a glance, exactly what changed about the query's actual logic and behavior, not its appearance.
No — purely cosmetic changes like keyword casing, indentation, and line breaks are ignored by default so you only see differences that affect the query's actual behavior.
It highlights that the JOIN order changed structurally; whether that specific reordering affects results depends on your database engine and the join types involved, which the tool flags for your review rather than assuming an answer.
It's built primarily for individual query statements; large procedural blocks with control-flow logic are better reviewed with a broader code diff tool alongside this one for the embedded queries themselves.
No, comparison is purely structural and textual — no query is ever executed, and no database connection is required or made.
No, all parsing and comparison logic runs locally in your browser.