You can control the visibility of your query by using the blue Share button in the top right of the app.
A modal will pop up where you can control the permissions of your query:
Query is private to you: Good for "scratch" work that others won't find useful.
Query can be viewed by your team: Most of your queries should be shared so that your teammates can find and leverage your work.
Query can be edited by your team: Similar to above, but now your teammates can make changes to your query too.
You can also drag your query into the Shared queries area and it will become viewable by your team. More on that in shared folders.
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