You’d like to query JSON document database using SQL-like syntax?
Couchbase has N1QL for you.
N1QL is a declarative query language that extends SQL for JSON. You can query data via native framework and language integration, a fluent API, or the JDBC/ODBC drivers.
N1QL enables you to query JSON documents without any limitations – sort, filter, transform, group, and combine data with a single query. That’s right. You can combine data from multiple documents with a JOIN. That flexible data model you were promised? This is it. You’re no longer limited to “single table” and “table per query” data models.
N1QL Tutorial is a great resource to learn the concepts of querying JSON documents using SQL-like syntax. Here are some examples:
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SELECT children[0].fname AS cname
FROM tutorial
WHERE fname='Dave'
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SELECT fname, age, age/7 AS age_dog_years
FROM tutorial
WHERE fname = 'Dave'
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SELECT relation, COUNT(*) AS count
FROM tutorial
GROUP BY relation
HAVING COUNT(*) > 1
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SELECT t.relation, COUNT(*) AS count, AVG(c.age) AS avg_age
FROM tutorial t
UNNEST t.children c
WHERE c.age > 10
GROUP BY t.relation
HAVING COUNT(*) > 1
ORDER BY avg_age DESC
LIMIT 1 OFFSET 1
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SELECT
product.name,
COUNT(reviews) AS reviewCount,
ROUND(AVG(reviews.rating),1) AS AvgRating,
category
FROM reviews AS reviews
JOIN product AS product
ON KEYS reviews.productId
UNNEST product.categories AS category
WHERE category = "Appliances"
GROUP BY category, product
ORDER BY AvgRating
DESC LIMIT 3
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Alternatively you can use Couchbase Query Workbench. The query workbench provides a rich graphical user interface to prepare and execute simple to complex N1QL queries. It provides a convenient way to perform query development by enabling you to browse, create, and run N1QL statements, and view results.
Want to learn how to get started?
Learn all about it in this brief session with Eben Haber:
Ask your questions at Stack Overflow or Couchbase Forums.
You can also follow us at @couchbasedev and @couchbase.
Enjoy!
