Avro version incompatabilites - storage

I can't find much info about file compatabilities/incompatabilities between Avro files serialized with different versions of the Apache or other Avro libraries.
I would like to know if Avro is a suitable long time storage format for original data or not?

Related

Splitting an Avro file?

The Avro-Tools package provides an easy way to concatenate multiple avro files together, however there doesn't seem to be an easy way to split files.
Does anyone know of a simple command-line tool that allows one to split an Avro file?

Is there a way, from Java/Scala code, to retrieve the version of Avro library?

I'm not 100% sure that e.g. version 1.7.7 of Avro can read files produced by 1.9.2 or 1.8.2. So I'd rather keep somewhere in meta information the version of avro that was used when creating a file.
But I don't see how it is possible, without tweaking build files and creating some kind of resource (it's pretty simple in gradle).
As you can see in Get jar version in runtime, version can be retrieved, at least when it's provided.
So, in this specific case, the following line:
(new org.apache.avro.Schema.Parser).getClass.getPackage.getImplementationVersion
Returns a version string; in my specific case it is "1.7.7".

How does QGIS read in projection information from hdf5 files? Projection info not recognized

When i bring an HDF5 file into QGIS that contains raster information, the data visually appear however spatially, they are not projected properly. QGIS does not read the spatial CRS information embedded in the hdf5 file.
Does anyone know what QGIS looks for in terms of syntax and attributes (and where) when it opens an HDF5 file? I'd like to adjust my HDF5 files so that the CRS information reads and QGIS can project the data.
Thank you for any direction
Leah
According to the GDAL documentation for the HDF5 driver there is no standard way of doing so.
But something worth trying is to peek at a file which does work for you. Unfortunately i don't have a GDAL driver which can write HDF5 files, but i can create a HDF4 file. If i convert a (georeferenced) Geotiff to HDF4 with GDAL, QGIS reads it correctly, with CRS information etc.
GDAL creates four global attributes, it might be worth trying to create those in your HDF5 file. I'm not sure if all of them are necessary, the 'Signature' doesn't seem crucial. Though it really depends on the implementation of HDF5 in QGIS, it could be completely different compared to HDF4.

Are there any Java libraries than can read hierarchical xmp data from files?

I tried looking into Apache Tika, but it seems to flatten XMP keywords to a single level.
Are there any Java libraries than can read hierarchical xmp data from files? Even just image files would suffice, but the more file types the better.

Source code storage in TFS2010

How source code is stored in SQL server for TFS2010.Is it possible to see it by digging the Database?
Versions of checked-in files are indeed stored in the database, which is basically just a simple blob store that contains a mix of the entire version controlled files as well as "deltas" between them.
That is to say that the server will occasionally store the differences between two versions of the files using a binary delta algorithm. For example, for a file $/Project/File.txt, version 1 may be stored intact but version 2 may be stored as the delta from version 1. When a client requests version 2 of $/Project/File.txt, the file may be reassembled from deltas before delivery.
The database is intended to be treated as an opaque data store and is generally not supported. In order to interact with your version control programmatically, it is intended that you would use the very rich APIs that are available for communicating with Team Foundation Server, either from .NET
or from Java.

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