using System;
using System.IO;
using System.Text.RegularExpressions;

public class Test
{
	public static void Main()
	{
		var str = "FIND files where file2=29 AND file32=\"12\" OR file623134=\"file23\"";
		var rx = new Regex(@"\bfile(\d+)=""?(\w+)""?");
        var result = rx.Replace(str, "(FILE_ID=$1 AND FILE_VALUE=$2)").Replace("FIND files where", "SELECT * FROM [FILES] WHERE");
        Console.WriteLine(result);
	}
}