![]() ![]() Now let's look at another query that performs iteration over children in the collection. In this case we are using this function to return child objects at $.children path. entire JSON sub-objects or sub-arrays within the documents), while JSON_VALUE returns scalars (i.e. The main difference is that it returns JSON fragments (e.g. JSON_QUERY function is similar to JSON_VALUE. The following DocumentDB query returns all children objects from family documents:Įquivalent Sql server query would look like: ![]() If you have complex JSON documents you might want to access various sub-entities such as children or pets in the example above. WHERE JSON_VALUE(doc, '$.id') IN ('AndersenFamily', 'WakefieldFamily') WHERE Families.id IN ('AndersenFamily', 'WakefieldFamily')Įquivalent Sql Server query would use standard T-Sql IN predicate: For example, this query returns all family documents where the id is one of "WakefieldFamily" or "AndersenFamily". In DocumentDB the IN keyword can be used to check whether a specified value matches any value in a list. Sql Server will use path syntax in the property names and lookup properties on the same paths. If you don’t want to use path you can name you property following path syntax: This might help if you have a lot of properties in the same query. SQL Server provides you separate function OPENJSON that can open json document in the doc column and you can specify what fields you want to use as well as the types of the fields:īeside the fact that fields are strongly types you can directly use their aliases in the queries. WHERE JSON_VALUE(f.doc, '$.address.city') = JSON_VALUE(f.doc, '$.address.state') SELECT JSON_VALUE(f.doc, '$.id') AS Name, JSON_VALUE(f.doc, '$.address.city') AS City "firstName": "Henriette Thaulow", "gender": "female", "grade": 5, id int identity constraint PK_JSON_ID primary key,ĭoc nvarchar(max) CONSTRAINT CHECK (ISJSON(doc)>0) Since Sql Server does not have collections we will create simple table that would contain documents same as in the I have used DocumentDB as a reference because it has easy-to-understand syntax, so I believe that you will easily understand how to use equivalent Sql Server queries.ĭocumentDB stores JSON documents in collections. In this post, I will show you some queries that can be executed in DocumentDB and equivalent Sql Server queries. Sql Server provides built-in functions for accessing JSON fields (JSON_VALUE), fragments (JSON_QUERY) and opening JSON documents (OPENJSON). Being a database designed for JSON and JavaScript, DocumentDB uses JavaScript as its underlying type system and supports both SQL as well as JavaScript queries.īoth SQL Server 2016 and DocumentDB enable you to query JSON documents.DocumentDB has nice syntax for querying JSON documents – you can find some good examples on JSON can be used with all components/features in SQL Server such as In-memory OLTP, Column store, temporal, etc.ĭocumentDB is a write optimized and schema agnostic document database purpose built for JSON and JavaScript it does not require any schema or secondary indices in order to serve queries. ![]() ![]() JSON support in SQL Server uses standard T-SQL syntax for querying JSON data with some additional built-in functions that enables you to read values of objects from JSON data. SQL Server 2016/Azure SQL Db are relational databases that will have support for handling JSON data. In this article I will show you similarities and differences between SQl Server JSON and DocumentDB query syntax. SQL Server JSON query syntax compared to DocumentDB ![]()
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