In MySQL, we can use the ->> operator to extract a value from a JSON document, and unquote that value.
We provide the column that contains the JSON document to the left of the operator, and the path to the value that we want to extract to the right.
The ->> operator is equivalent to JSON_UNQUOTE(JSON_EXTRACT()), and it provides the same results.
In MySQL, we can use the -> operator to extract data from a JSON document.
We provide the column that contains the JSON document to the left of the operator, and the path to the value that we want to extract to the right.
The -> operator is an alias for the two-argument form of the JSON_EXTRACT() function.
In MySQL, the MEMBER OF() operator tests whether or not a value is a member of a given JSON array.
It returns true (1) if the array contains the value, and false (0) if it doesn’t.
The MEMBER OF() operator was added in MySQL 8.0.17.
In MySQL, JSON_OVERLAPS() is a function that tests whether or not two JSON documents have any key-value pairs or array elements in common.
The function returns true (1) if the documents have any key-value pairs or array elements in common, and false (0) if they don’t.
The JSON_OVERLAPS() function was added in MySQL 8.0.17.
In MySQL, JSON_MERGE() is a deprecated function that merges two or more JSON documents and returns the result.
It was deprecated in MySQL 8.0.3 and is subject to removal in a future release.
Fortunately, the JSON_MERGE_PRESERVE() function was added in MySQL 8.0.3 as a synonym for JSON_MERGE(), and it therefore does the same thing that JSON_MERGE() does/did.
Therefore, instead of using JSON_MERGE(), use JSON_MERGE_PRESERVE() instead.
Alternatively, you can use JSON_MERGE_PATCH(), which performs an RFC 7396 compliant merge of two or more JSON documents, without preserving members having duplicate keys.
In MySQL, JSON_TABLE() is a built-in function that converts JSON data into a relational form.
In other words, it lets you return a JSON document as a table.
The JSON_TABLE() function was introduced in MySQL 8.0.
SQLite provides several functions for inserting, setting, and replacing values in a JSON document. Specifically, it provides json_insert(), json_set(), and json_replace().
These functions perform similar tasks, and you can sometimes use them interchangeably to a certain point.
But there is definitely a clear difference between each function.
When using SQLite, we can use the following methods to extract data from a JSON document.
The -> and ->> operators were introduced in SQLite version 3.38.0, which was released on 22 February 2022. Both operators are used for extracting subcomponents of JSON. But there’s a subtle difference between them.
Below is a full list of JSON functions and JSON operators available in SQLite.