If you’re not sure about the concept and use of ad-hoc Query, do your own research on the technical documentation.
To put it simply: Ad Hoc query (Ad Hoc) is a flexible choice of query conditions by users according to their own needs, and the system can generate corresponding statistical reports according to the choice of users.
The biggest difference between AD hoc query and ordinary application query is that ordinary application query is customized, while AD hoc query is user-defined by users.
AD hoc queries are those defined by the user when using the system according to their needs at the time.
For AD hoc queries, what the user needs to query is not known at the beginning, so queries require more dimensions, and queries are often constructed at run time.
Druid’s queries support AD hoc queries well, but they also introduce some complexity and a learning curve.
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