Yii2 find one

ActiveRecord is the base class for classes representing relational data in terms of objects, yii2 find one. Active Record implements the Active Record design pattern. The object's attributes are mapped to the columns of the corresponding table. Referencing an Active Record attribute is equivalent to accessing the corresponding table column for that record.

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community. Already on GitHub? Sign in to your account. But findOne behaves strangely in the case. And I didn't find the description of this behavior in any documentation. The text was updated successfully, but these errors were encountered:.

Yii2 find one

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community. Already on GitHub? Sign in to your account. I discovered this recently when I noticed performance degradation on large datasets. This may seem insignificant, but according to how indexes work, it may cause huge performance degradation on large datasets. The reason is, that SQL in [1] will not stop column scan when founds first match and will continue until whole column scanned. On tables with millions of records this has significant negative performance impact. So variant [1] works flawlessly only on columns with primary or unique indexes , where the ID uniqueness is guaranteed. It performs badly on columns with common KEY indexes because uniqueness cannot be guaranteed. However, since the method name one or findOne suggests it will return only one first match it makes no sense to continue scanning after matching first record. So by adding LIMIT 1 it would stop scanning also on non-unique indexes and ensure optimal performance. Or did i miss some reason why it may not be added? If not I guess this should be emphasized in documentation so developers would realize described performance difference. I have seen couple of complaints about Yii2 DB performace around and this issue could be possibly related.

User Contributed Notes 1. Whether there is any handler attached to the event.

Active Record provides an object-oriented interface for accessing and manipulating data stored in databases. An Active Record class is associated with a database table, an Active Record instance corresponds to a row of that table, and an attribute of an Active Record instance represents the value of a particular column in that row. Instead of writing raw SQL statements, you would access Active Record attributes and call Active Record methods to access and manipulate the data stored in database tables. For example, assume Customer is an Active Record class which is associated with the customer table and name is a column of the customer table. You can write the following code to insert a new row into the customer table:. The above code is equivalent to using the following raw SQL statement for MySQL, which is less intuitive, more error prone, and may even have compatibility problems if you are using a different kind of database:. In this tutorial, we will mainly describe the usage of Active Record for relational databases.

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community. Already on GitHub? Sign in to your account. I'm new to Yii and I've been just changing default User class to make it depend on database rather than on static attribute.

Yii2 find one

ActiveRecord is the base class for classes representing relational data in terms of objects. Active Record implements the Active Record design pattern. The object's attributes are mapped to the columns of the corresponding table. Referencing an Active Record attribute is equivalent to accessing the corresponding table column for that record. As an example, say that the Customer ActiveRecord class is associated with the customer table. This would mean that the class's name attribute is automatically mapped to the name column in customer table. In this example, Active Record is providing an object-oriented interface for accessing data stored in the database. But Active Record provides much more functionality than this.

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By default, Active Record uses the db application component as the DB connection to access and manipulate the database data. The methods described above all work on individual Active Record instances, causing inserting or updating of individual table rows. Fields can be nested, separated with dots. The benefit of using link is even more obvious when a relation is defined via a junction table. The default implementation of this method returns the public object member variables indexed by themselves. For more details and usage information on ActiveRecord, see the guide article on ActiveRecord. The fully qualified name of this class. The names of the relations of primary models to be loaded from database. Warning: If you need to pass user input to these methods, make sure the input value is scalar or in case of array condition, make sure the array structure can not be changed from the outside:. If true , the latest data will be populated to this active record. If the latter, the corresponding attribute values will be modified accordingly. An event that is triggered after the record is created and populated with query result. Hope someone find this helpful. Call init. When working with relational data, you often need to establish relationships between different data or destroy existing relationships.

These methods can be chained together.

However, it may suffer from a performance issue when you need to access the same relation property of multiple Active Record instances. Whether the saving succeeded i. It is a common task to increment or decrement a column in a database table. Whether at least one of the models is successfully populated. You can specify a different join type e. There is no automatic conversion for the values loaded from HTTP request or set directly via property access. The primary keys of the associated database table. List of attributes that need to be saved. Whether the record is new and should be inserted when calling save. Go to Top. Version 2.