Comparing two different properties in GQL

Question

The following two GQL queries work:

SELECT * FROM Customer WHERE FirstName = "John"
SELECT * FROM Customer WHERE Rating > 4.0

But, when I combine them...

SELECT * FROM Customer WHERE FirstName = "John" AND Rating > 4.0

... I get an empty result set even though running the queries individually finds the entity that I am looking for. How do I compare more than one property?

Here's what I've done:

I made sure that at least one entity exists where both is true.

gql

I created an index for the properties:

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Are the first two result sets disjoint? (i.e. the intersection is empty?) — fferri, Jun 19 '15 at 00:16
People down vote without leaving a reason why. If you leave a reason, I can work on making this a better question. :) — arao6, Jun 30 '15 at 20:12

score 3 · Accepted Answer · answered Jun 23 '15 at 19:03

Patrick Costello at Google answered my question:

You need an index on exactly (FirstName, Rating). Your current index cannot answer that query.

Basically, the problem was that I created an index on all the properties. However, each "type" of query (in this case, a query comparing FirstName and Rating) needs its own index (i.e. an index with just FirstName and Rating). I hope this helps someone!

Comparing two different properties in GQL

1 Answers1