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I've an entity in Google Cloud Datastore. One of the properties is array of strings. For example:

property: skills

Entity 1:
value: ["mysql","sqlserver","postgresql","sqllite","sql-server-2008","sql"]

Entity 2:
value: ["css","css3"]

Now, I need to query for those entities that contain array elements css*

In typical SQL, it'll be select * from kindName where skills like 'css%'

I tried select * from kindName where skills = 'css', which works fine but how can I get entities that have css* elements similar to the SQL query?

Or

What's the best way to model the data for this?

Dan McGrath
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Sahas
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  • Make sure to write `css` every time `css3` is used? Or try queries by prefix, .e.g http://stackoverflow.com/questions/17702958/ndb-querying-results-that-start-with-a-string – Dmytro Sadovnychyi Oct 13 '16 at 09:18

1 Answers1

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You can do inequality range checks on a single indexed property as given in the example below. Range checks on strings are essentially how you can perform prefix searching on strings.

SELECT * from yourKind WHERE skills >= "css" AND skills < "cst"

As an example, here is the query performed on some sample data I created in the UI Console for Cloud Datastore:

Example performed in the Google Cloud Datastore's console

Dan McGrath
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