SQL Dialect Converter — Convert Between MySQL, PostgreSQL, SQL Server, SQLite & Oracle
Paste SQL written for one database and convert it to another dialect instantly. The converter handles functions, LIMIT/TOP/FETCH clauses, identifier quoting, data types, auto-increment syntax, NULL handling, date/time functions, string concatenation, and more. A detailed change log, warnings, and confidence score let you verify every transformation. Everything runs in your browser — your SQL is never uploaded.
Converted Output
What This Tool Does
Converts SQL queries between MySQL, PostgreSQL, SQL Server (T-SQL), SQLite, and Oracle dialects in your browser — handling data type differences, function names, and syntax variations automatically.
Who This Is For
- Developers migrating databases between platforms who need to port their query library
- Data engineers porting ETL pipelines between cloud database providers
- Backend engineers who write queries in one dialect but deploy to multiple database targets
- Anyone who finds a MySQL example online and needs the PostgreSQL equivalent
Example: Input: MySQL: SELECT * FROM users LIMIT 10 → Output: SQL Server: SELECT TOP 10 * FROM users — with all syntax differences converted and dialect-specific function names mapped
What Are SQL Dialects?
SQL (Structured Query Language) is standardized by ANSI/ISO, but every major database vendor extends it with proprietary syntax. MySQL, PostgreSQL, SQL Server, SQLite, and Oracle each have their own functions, pagination syntax, quoting styles, data types, and DDL conventions. When migrating between databases or writing cross-platform queries, these differences create friction. A dialect converter automates the mechanical translation so you can focus on logic and semantics.
Common Syntax Differences
| Feature | MySQL | PostgreSQL | SQL Server | SQLite | Oracle |
|---|---|---|---|---|---|
| Current Timestamp | NOW() | CURRENT_TIMESTAMP | GETDATE() | CURRENT_TIMESTAMP | SYSTIMESTAMP |
| Row Limit | LIMIT n | LIMIT n | TOP n / FETCH | LIMIT n | FETCH FIRST n ROWS ONLY |
| NULL Coalesce | IFNULL(a,b) | COALESCE(a,b) | ISNULL(a,b) | IFNULL(a,b) | NVL(a,b) |
| String Concat | CONCAT(a,b) | a || b | a + b | a || b | a || b |
| Identifier Quoting | `col` | "col" | [col] | "col" or `col` | "col" |
| Auto Increment | AUTO_INCREMENT | GENERATED BY DEFAULT AS IDENTITY | IDENTITY(1,1) | AUTOINCREMENT | GENERATED BY DEFAULT AS IDENTITY |
| Boolean Literals | TRUE / FALSE | TRUE / FALSE | 1 / 0 | 1 / 0 | 1 / 0 |
How the Converter Works
The converter uses a two-tier approach. First, it tokenizes your SQL — splitting it into keywords, identifiers, string literals, comments, and operators while tracking parentheses depth. String literals and comments are left untouched to prevent accidental corruption. Then it applies dialect-specific transformation rules as data-driven mappings: function replacements, clause restructuring (LIMIT to FETCH NEXT, TOP to LIMIT), identifier re-quoting, data type mapping, and DDL keyword substitution. Each rule logs its action to the change log. Constructs that can't be safely converted generate warnings and are preserved in the output.
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🔒 Your SQL Stays Private
This tool runs entirely in your browser. No SQL is ever sent to a server. There are no analytics libraries that transmit query content. Your data never leaves your machine.