![]() ![]() $things = App\Models\Thing::whereJsonContains('meta->many', 'Wardrobe')->first() ![]() all things where the meta.many array contains Wardrobe $things = App\Models\Thing::where('meta->single', 'Gingerbread')->get() all things where the meta.single property matchs 'Gingerbread' $things = App\Models\Thing::select()->get() These are the SQL queries we used before translated to Eloquent: // all things It's up to you if you prefer work with an associative array or with an object of stdClass: 'array', In the App\Models\Thing class you define a caster for the JSON field. $table->foreignIdFor(\App\Models\User::class) The migration below describes the table we used before: id() With the $casts property on your Model you specify how you want to work with the decoded JSON in PHP. Eloquent has supported JSON columns since Laravel 5.7, which means it translates a human readable syntax to a grammar specific to MySQL or other database engines. Let's be honest, who writes raw SQL these days? Most likely you rely on some kind of abstraction layer to access your database. INSERT INTO things (user_id, meta) VALUES(100, ' | If you take a look at the INSERT statements below, you will notice that the values we insert into the meta fields look like strings. We also need some dummy data to play around with. (Feel free to ignore the user_id field: it's just there to show that we can mix relational data and JSON objects in a single table.) CREATE TABLE things (Ĭreated_at DATETIME DEFAULT CURRENT_TIMESTAMP ![]() To understand what you can do with JSON columns, let's create a table with a meta JSON field and also a reference to an imaginary users table. This hybrid approach is not new - PostgreSQL has supported JSON since 2013. MySQL has had a built-in JSON column type since 5.7, and a lot of improvements have been introduced with the 8.0 release. But the truth is you don't need another database. But what if there is some parts of your data that does not fit into a relational model - data that does not follow a strict schema? You could opt for a NoSQL database like MongoDB, that is optimized for storing JSON-like documents. MySQL, like any other relational database, is great at modelling data structures and making connections between them. Learn about JSON columns in MySQL and how to use them in Laravel. INDEX i3 ( (JSON_VALUE(items, '$.Take care. INDEX i2 ( (JSON_VALUE(items, '$.price' RETURNING DECIMAL(5,2))) ), INDEX i1 ( (JSON_VALUE(items, '$.name' RETURNING CHAR(50))) ), Here’s the example used in the release notes: CREATE TABLE inventory( A call to JSON_VALUE( json_doc, path RETURNING type) is equivalent to calling CAST( JSON_UNQUOTE( JSON_EXTRACT( json_doc, path) ) AS type). IndexesĪs mentioned in the MySQL 8.0.21 release notes, the JSON_VALUE() function simplifies the creation of indexes on JSON columns. Specifying them in the wrong order results in a syntax error. If used, ON EMPTY must precede any ON ERROR clause. DEFAULT value ON ERROR: This is the value returned its value must match that of the return type.NULL ON ERROR: JSON_VALUE() returns NULL this is the default behaviour.The following can be used to specify what happens when an error occurs: ERROR ON EMPTY: The function throws an error.The value’s type must match that of the return type. DEFAULT value ON EMPTY: the provided value is returned.NULL ON EMPTY: The function returns NULL this is the default behaviour.However, the following options can be used to explicitly specify what should happen when no data is found at the given path: Empty Resultsīy default, if no data is found at the specified path, NULL is returned: SELECT JSON_VALUE( If you don’t specify the return type, the return type is VARCHAR(512). ![]() Here’s an example of specifying the return type: SELECT JSON_VALUE( Here’s an example of getting a value from an embedded object: SELECT JSON_VALUE( ', '$.scores' ) Īrrays are zero based, so 1 returns the second element ( 0 would return the first). The syntax goes like this: JSON_VALUE(json_doc, path ) The function was introduced in MySQL 8.0.21. In MySQL, the JSON_VALUE() function extracts a value from a JSON document at the specified path. ![]()
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