How can I Query JSON Data in MySQL Based on Specific Field Values?
Querying JSON Data in MySQL
Problem:
You have a MySQL table with a column that stores JSON objects. You need to run queries that filter results based on specific JSON field values.
Solution: Using json_extract Function
MySQL 5.7 and later introduced the json_extract function, which allows you to extract specific values from JSON objects stored in a column. This allows you to perform queries like the following:
<code class="sql">SELECT user_id, json_data FROM articles WHERE json_extract(json_data, '$.title') LIKE '%CPU%';</code>
Example:
Consider the following table:
<code class="sql">CREATE TABLE articles ( id int NOT NULL, user_id int NOT NULL, json_data json NOT NULL ); INSERT INTO articles (id, user_id, json_data) VALUES (1, 1, '{"url":"https://www.cpubenchmark.net/","title": "CPU Benchmarks"}'), (2, 1, '{"url":"http://www.ebay.com/sch/CPUs-Processors-/164/i.html","title": "Computer and Processors"}'), (3, 2, '{"url":"https://www.youtube.com/watch?v=tntOCGkgt98","title": "Funny Cats Compilation"}');</code>
Running the query shown above will return the following result:
<code class="sql">+---------+--------------------------------------------------------------------------------------------------+ | user_id | json_data | +---------+--------------------------------------------------------------------------------------------------+ | 1 | {"url":"https://www.cpubenchmark.net/","title": "CPU Benchmarks"} | +---------+--------------------------------------------------------------------------------------------------+</code>
This demonstrates how the json_extract function can be used to filter JSON data in MySQL.
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