If I run StarData[], Mathematica will download the entire database from its server, which is quite a lot of data and takes some time:

"Downloading entities 17501 through 20000 of 107522 ...."

Eventually it downloads everything and displays it as a list of entities. However, the next time I start the kernel and execute StarData[], Mathematica will download the entire database again. This is a huge waste of resources. Is it possible to keep the downloaded curated data between Mathematica sessions?

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    $\begingroup$ Related: 64130 $\endgroup$ – shrx Apr 3 '15 at 10:28
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    $\begingroup$ Also strongly related: (3459) $\endgroup$ – bobthechemist Apr 3 '15 at 14:09

There are two types of curated data in the Wolfram Language, the classic "paclet" functions like ChemicalData and the EntityValue Knowledgebase functions like StarData, and only the former supports the "Preload" mechanism. If the first item in the ref 'details' section of the ref pages says The specified "name" in XXXXData can be an Entity, EntityClass, or canonical name. then the function is a Knowledgebase function.

You can always save the results of StarData[] with a function like DumpSave or Save, and simply Get["file"] in a future session, though I understand there are plans in the works for all Knowledgebase functions like StarData to have a caching mechanism in the future.


In Mathematica 10.4.0 (February 26, 2016), StarData[] and similar, e.g. MinorPlanetData[], is now cached. It downloads only once, no matter whether Kernel is stopped or no. Partial download also is cached.

  • $\begingroup$ Thanks for the update, I can confirm it keeps the data between Mathematica sessions and kernel restarts. $\endgroup$ – shrx Mar 26 '16 at 21:15

You used to be able to Preload paclet data

PacletName["All", "Preload"]

For e.g. chemical data you'd type:

ChemicalData["All", "Preload"]

See also this support article

I've heard rumors (but haven't tried it myself) that in v10 this doesn't work anymore.

  • $\begingroup$ Unfortunately, for StarData I get Missing["UnknownEntity", {"Star", "All"}]. With ChemicalData it seems to download the data but the next time I start Mathematica it downloads it again. v10.0.2 $\endgroup$ – shrx Apr 3 '15 at 11:32
  • $\begingroup$ In 10.1, only the index is downloaded and installed into Paclets\Repository. The data itself remains remote until accessed explicitly. $\endgroup$ – Jinxed Apr 3 '15 at 11:45
  • $\begingroup$ @shrx is this on your RPi? can preload (e.g) ElementData on 10.0.2 Windows but it appears to ignore preloading on the RPi for me. $\endgroup$ – bobthechemist Apr 3 '15 at 14:10
  • $\begingroup$ @bobthechemist no, this was on my Linux machine at work. $\endgroup$ – shrx Apr 3 '15 at 15:55

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