EF Migration History Decoder

using System;
using System.IO;
using System.IO.Compression;
using System.Linq;
using System.Text;

namespace TestMigrationHistory
{
    class Program
    {
        static void Main(string[] args)
        {
            var ctx = new TestContext();

            var modelBase64 = ctx.Database.SqlQuery<string>(@"
                        DECLARE @binaryContent VARBINARY(MAX);
                        SELECT @binaryContent = Model FROM [__MigrationHistory];
                        SELECT CAST('' AS XML).value( 'xs:base64Binary(sql:variable(''@binaryContent''))', 'varchar(max)' ) AS base64Content;"
                    ).FirstOrDefault();

            if (modelBase64 == null) return;

            var bytes = Convert.FromBase64String(modelBase64);
            var uncompressed = Decompress(bytes);

            var edmx = Encoding.UTF8.GetString(uncompressed);
            File.WriteAllText(@"d:\edmx.xml", edmx);
        }

        static byte[] Decompress(byte[] gzip)
        {
            using (var stream = new GZipStream(new MemoryStream(gzip), CompressionMode.Decompress))
            {
                const int size = 4096;
                var buffer = new byte[size];

                using (var memory = new MemoryStream())
                {
                    int count;
                    do
                    {
                        count = stream.Read(buffer, 0, size);
                        if (count > 0)
                        {
                            memory.Write(buffer, 0, count);
                        }
                    }

                    while (count > 0);
                    return memory.ToArray();
                }
            }
        }
    }
}