MySQL Parser

A MySQL-compatible SQL parser extracted from TiDB, now available as a standalone Go module with WASM support.

Worth mentioning the database built on top of mysql-parser: MIST

Features

• MySQL Compatibility: Supports MySQL 5.7+ SQL syntax
• Full AST Support: Complete Abstract Syntax Tree generation
• Visitor Pattern: Easy AST traversal and manipulation
• WASM Support: Runs in WebAssembly environments
• Type Safety: Proper handling of MySQL data types
• Cross-Platform: Optimized for both native and WASM execution

Module Information

Module Path: github.com/abbychau/mysql-parser

This parser provides MySQL-compatible SQL parsing with full AST support and two parser driver options:

1. Test Driver (test_driver) - Lightweight, basic functionality
2. Full Driver (parser_driver) - Complete functionality with WASM compatibility

Installation

go get github.com/abbychau/mysql-parser

Usage Examples

Basic Usage with Test Driver

package main

import (
    "fmt"
    "github.com/abbychau/mysql-parser"
    "github.com/abbychau/mysql-parser/ast"
    _ "github.com/abbychau/mysql-parser/test_driver"
)

func main() {
    p := parser.New()
    sql := "SELECT name, age FROM users WHERE age > 25"
    
    stmtNodes, _, err := p.ParseSQL(sql)
    if err != nil {
        fmt.Printf("Parse error: %v\n", err)
        return
    }
    
    fmt.Printf("Successfully parsed %d statements\n", len(stmtNodes))
}

Advanced Usage with Full Parser Driver

package main

import (
    "fmt"
    "github.com/abbychau/mysql-parser"
    "github.com/abbychau/mysql-parser/ast"
    _ "github.com/abbychau/mysql-parser/parser_driver"
)

// ColumnExtractor implements ast.Visitor to extract column names
type ColumnExtractor struct {
    ColNames []string
}

func (v *ColumnExtractor) Enter(in ast.Node) (ast.Node, bool) {
    if name, ok := in.(*ast.ColumnName); ok {
        v.ColNames = append(v.ColNames, name.Name.O)
    }
    return in, false
}

func (v *ColumnExtractor) Leave(in ast.Node) (ast.Node, bool) {
    return in, true
}

func main() {
    p := parser.New()
    sql := "SELECT users.name, orders.total FROM users JOIN orders ON users.id = orders.user_id"
    
    stmtNodes, _, err := p.ParseSQL(sql)
    if err != nil {
        fmt.Printf("Parse error: %v\n", err)
        return
    }

    // Extract column names using visitor pattern
    extractor := &ColumnExtractor{}
    stmtNodes[0].Accept(extractor)
    
    fmt.Printf("Extracted columns: %v\n", extractor.ColNames)
}

WASM Usage

For WebAssembly applications, use the full parser driver:

package main

import (
    "syscall/js"
    "github.com/abbychau/mysql-parser"
    "github.com/abbychau/mysql-parser/ast"
    _ "github.com/abbychau/mysql-parser/parser_driver"
)

func parseSQL(this js.Value, args []js.Value) interface{} {
    sqlText := args[0].String()
    
    p := parser.New()
    stmtNodes, _, err := p.ParseSQL(sqlText)
    if err != nil {
        return map[string]interface{}{
            "success": false,
            "error":   err.Error(),
        }
    }
    
    return map[string]interface{}{
        "success": true,
        "count":   len(stmtNodes),
    }
}

func main() {
    js.Global().Set("parseSQL", js.FuncOf(parseSQL))
    select {} // Keep the program running
}

Project Structure

github.com/abbychau/mysql-parser/
├── ast/                    # Abstract Syntax Tree definitions
├── charset/               # Character set support
├── mysql/                 # MySQL constants and utilities
├── parser_driver/         # Full parser driver (WASM-compatible)
├── test_driver/          # Lightweight test driver
├── wasm-demo/            # WebAssembly demo application
└── docs/                 # Documentation

Parser Drivers

Test Driver (test_driver)

• Lightweight and minimal dependencies
• Basic AST node support
• Suitable for simple parsing tasks
• Import: _ "github.com/abbychau/mysql-parser/test_driver"

Full Parser Driver (parser_driver)

• Complete functionality with proper type handling
• WASM-compatible (no CGO or unsafe operations)
• Supports all MySQL data types and expressions
• Full type system including Datum, FieldType, MyDecimal, Time
• Comprehensive error handling and type conversions
• Self-contained with no external dependencies
• Import: _ "github.com/abbychau/mysql-parser/parser_driver"

Building for WASM

cd wasm-demo
GOOS=js GOARCH=wasm go build -o parser.wasm main.go

The parser_driver package is specifically designed to work in WASM environments. The demo includes a web interface for testing SQL parsing in the browser.

License

Apache License 2.0 - see LICENSE file for details.

Original Source

This parser is based on TiDB's SQL parser component, modified for standalone use and WASM compatibility.