It increases the complexity of any code you write to do it, and the developer who needs to take over maintenance of your code after you have moved on to another project will curse your name. Storing data in a JSON document when you eventually want to use SQL expressions to search or update individual fields within the JSON document is a costly mistake. Now compare how difficult that is to: UPDATE content SET status = 1 WHERE name = 'Jack' Using this in an UPDATE looks like this: mysql> update example set content = json_set(content, concat(json_unquote(json_search(json_extract(content, '$.name'), 'one', 'Jack')), '.status'), '1') JSONSET () Syntax Here is the syntax of the MySQL JSONSET () function: JSONSET(json, path, value, path2, value2. In MySQL 8.0.4, the optimizer can perform a partial, in-place update of a JSON. It is equivalent to a combination of JSONINSERT () and JSONREPLACE (). The functions in this section modify JSON values and return the result. Document Store and CRUD We know that MySQL 8.0 Document Store handles JSON documents with CRUD operations. Now use it in a JSON_SET() call: mysql> select json_pretty(Ĭoncat(json_unquote(json_search(json_extract(content, '$.name'), 'one', 'Jack')), '.status'), In MySQL, the JSONSET () function inserts or updates data in a JSON document and return a new JSON document. Let’s start with some info about how MySQL Document Store handles JSON documents. status and you can get the full path to the field you want to update: mysql> select concat(json_unquote(json_search(json_extract(content, '$.name'), 'one', 'Jack')), '.status') as path from example Then you can search that array to get the array position: mysql> select json_search(json_extract(content, '$.name'), 'one', 'Jack') as root from example Here's a trick: You can extract the name field, and that turns into an array of those values: mysql> select json_extract(content, '$.name') as a from example mysql> select j.* from example cross join json_table(content, '$' columns( And that doesn't tell you the path to the element, it only allows you to return a specific row out of the array. To search for a key/value pair, you need to use JSON_TABLE() and that requires you upgrade to MySQL 8.0. How to Update JSON Data in MySQL How to Delete from a JSON Field in MySQL Validating JSON Data Improve the Performance of JSON Queries Tips for Working with JSON in MySQL Conclusion What is JSON and Why Should I Use It JSON stands for JavaScript Object Notation, and it’s a way to format and store data. Here is my sql code update posts set like if (jsoncontains (like,2,''), jsonremove (like,replace (jsonsearch (like,'one',2),''','')), jsonarrayappend (like,'',2) ) where id 3 My table After this sql code id 3 should be like id 2. mysql> select json_unquote(json_search(content, 'one', 'Jack')) as path from example 1 I want to update my raw with if-else condition. If "Jack" occurs in some other field, that would also be found. You can get the path to a JSON element with JSON_SEARCH(), but you can only search by value, not by a key/value pair. The solution in that case depends on you knowing which array element your pseudo-record exists in. The question like yours has come up before on Stack Overflow, for example JSON update single value in MySQL table. mysql> select json_pretty(json_replace(content, '$.status', '1')) as j But still, if its a URL and it allows to get only certain prams based on request query params, then it can be done. Only picking partial object may not be possible. The JSON values stored in that column, are just a way to differenciate a row from another, nothing more. 1,168 22 38 What is the source of your JSON A URL or a variable You need complete object to traverse upon. But later, I was thinking about using index to speed up the queries, and because of that, change the JSON type to maybe a TEXT type to create a index with the 4 columns. So in this case, we can see that the array element is $ but if you didn't know that, you couldn't use this solution. From the beginning I'm using the filter column as a JSON type of MySQL. WHERE somecolumnsomevalue Notice the WHERE clause in the UPDATE syntax: The WHERE clause specifies which record or records that should be updated. You can use JSON_REPLACE() or JSON_SET(), but both require that you know the path to the field you want to change. The UPDATE statement is used to update existing records in a table: UPDATE tablename SET column1value, column2value2. Although JSON data should preferably be stored in a NoSQL database such as MongoDB, you may still encounter tables with JSON data from time to time. How to UPDATE a mySQL table with JSON Object in Node. I'm trying to write a cron job to update currencies rate in our MySQL database.This is very awkward, nearly impossible with MySQL's JSON functions. Towards Data Science 6 min read - 1 MySQL supports a native JSON data type that supports automatic validation and optimized storage and access of the JSON documents.
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