![]() $data = ' make it an object.Īrrays are comma-separated lists inside square brackets. setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION) I wrote some PHP to decode the JSON into an associative array with json_decode(), and then use the keys and values to insert into the MySQL table I created. Mysql> create table mytable (name varchar(20), eur numeric(9,2), e numeric(9,2)) 1 UPDATE t SET jsoncol JSONSET (jsoncol, '.name', 'Knut') WHERE id 123 This update can be performed as a partial update because it takes a JSON column ( jsoncol ), modifies one of its members, and then stores it into the same column as it reads from ( jsoncol ). ![]() I created a table in MySQL's test schema: mysql> use test 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. 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.Here's a demo. 1,168 22 38 What is the source of your JSON A URL or a variable You need complete object to traverse upon. 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. 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. WHERE somecolumnsomevalue Notice the WHERE clause in the UPDATE syntax: The WHERE clause specifies which record or records that should be updated. 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. Now compare how difficult that is to: UPDATE content SET status = 1 WHERE name = 'Jack' The UPDATE statement is used to update existing records in a table: UPDATE tablename SET column1value, column2value2. 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') Now use it in a JSON_SET() call: mysql> select json_pretty(Ĭoncat(json_unquote(json_search(json_extract(content, '$.name'), 'one', 'Jack')), '.status'), status and you can get the full path to the field you want to update: mysql> select concat(json_unquote(json_search(json_extract(content, '$.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, '$.name'), 'one', 'Jack') as root from example a normalized databse, gets you the data, and is simple to update, and if you dthen need json you can still build it. Here's a trick: You can extract the name field, and that turns into an array of those values: mysql> select json_extract(content, '$.name') as a from example json array Share Improve this question Follow asked at 10:54 ErickBest 113 1 7 why use json in the first place. How can I update the interests if there are multiple values to be updated Running the above update statement to update the Visual Arts interest results in an. mysql> select j.* from example cross join json_table(content, '$' columns( UPDATE table SET meta JSONREPLACE (meta, JSONUNQUOTE (JSONSEARCH (meta, 'all', 'oldname')), 'newname') This works because the JSONSEARCH returns one path. ![]() And that doesn't tell you the path to the element, it only allows you to return a specific row out of the array. To search for a key/value pair, you need to use JSON_TABLE() and that requires you upgrade to MySQL 8.0. mysql> select json_unquote(json_search(content, 'one', 'Jack')) as path from example If "Jack" occurs in some other field, that would also be found. You can get the path to a JSON element with JSON_SEARCH(), but you can only search by value, not by a key/value pair. The solution in that case depends on you knowing which array element your pseudo-record exists in. ![]() path has the following syntax: append lax strict. The question like yours has come up before on Stack Overflow, for example JSON update single value in MySQL table. A JSON path expression that specifies the property to update. mysql> select json_pretty(json_replace(content, '$.status', '1')) as j 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. You can use JSON_REPLACE() or JSON_SET(), but both require that you know the path to the field you want to change. This is very awkward, nearly impossible with MySQL's JSON functions. ![]()
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