# IBM i SQL Language Utilities
## Attribution
This module is vendored from the official **Code for IBM i** VS Code extension:
- **Project:** [vscode-db2i](https://github.com/codefori/vscode-db2i)
## Purpose
These SQL language utilities provide battle-tested parsing and tokenization for **Db2 for IBM i** SQL syntax. We use them in the IBM i MCP Server for:
### 1. **SQL Security Validation**
The MCP server needs to validate SQL queries for security purposes, especially in read-only mode. The vscode-db2i parser handles IBM i-specific SQL syntax that generic parsers don't support.=
### 2. **Token-Based Validation**
The `SQLTokeniser` class provides precise token-level parsing that distinguishes between:
- SQL keywords vs. identifiers
- String literals vs. SQL code
- Function calls vs. regular identifiers
- Comments vs. executable code
This eliminates false positives when validating forbidden keywords (e.g., detecting `DELETE` as a keyword vs. `'DELETE'` as a string literal).
### 3. **Statement Type Detection**
The `Document` and `Statement` classes provide accurate detection of SQL statement types (SELECT, INSERT, UPDATE, DELETE, CALL, etc.), which is critical for enforcing read-only restrictions.
## Related Projects
- [vscode-db2i](https://github.com/codefori/vscode-db2i) - VS Code extension for Db2 for IBM i
- [Code for IBM i](https://codefori.github.io/docs) - Development tools for IBM i
- [@ibm/mapepire-js](https://www.npmjs.com/package/@ibm/mapepire-js) - IBM i database driver (used by this MCP server)
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**Questions or Issues?**
- For SQL parser issues, check [vscode-db2i issues](https://github.com/codefori/vscode-db2i/issues)
- For MCP server issues, check [ibmi-mcp-server issues](https://github.com/IBM/ibmi-mcp-server/issues)
