Breach that number and, irrespective of your data, it will return a null. Simple dot-notation JSON queries return all their results as strings, and can only return up to 4000 characters. Obey these rules and what you get is the following: if your query matches a single value it’ll return that value, but if it matches multiple values it’ll return them as the elements of a JSON array. The JSON object key in your query must be a case-sensitive match for the object key whose value you are seeking to retrieve.As always, while this constraint must exist, it does not need to be enabled. Your column must be a JSON column, by which I mean that it must be signposted as containing JSON data by the existence of an IS JSON check constraint.Your table must have an alias you cannot choose to skip this step and simply use the table name.There are a few rules that you need to bear in mind: The simple dot-notation syntax is as follows: the table alias followed by a dot followed by a JSON column followed by one or more JSON object keys (if there is more than one object key, they must all be separated by dots). The dot-notation syntax allows you retrieve JSON values easily using a syntax that resembles that you’d use in an ordinary sql statement. We’ll come on to talk about all the exciting, high-powered functionality that we have for querying our data, but there are times when you need something really simple and reasonably straightforward. Once we’ve inserted our data into our table we’re ready to rock and roll.
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