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read($fields, $id)

read() is a method used to set the current model data (Model::$data)--such as during edits--but it can also be used in other circumstances to retrieve a single record from the database.

$fields is used to pass a single field name, as a string, or an array of field names; if left empty, all fields will be fetched.

$id specifies the ID of the record to be read. By default, the currently selected record, as specified by Model::$id, is used. Passing a different value to $id will cause that record to be selected.

read() always returns an array (even if only a single field name is requested). Use field to retrieve the value of a single field.

function beforeDelete($cascade) {
   ...
   $rating = $this->read('rating'); // gets the rating of the record being deleted.
   $name = $this->read('name', $id2); // gets the name of a second record.
   $rating = $this->read('rating'); // gets the rating of the second record.
   $this->id = $id3; //
   $this->read(); // reads a third record
   $record = $this->data // stores the third record in $record
   ...
}

1. function beforeDelete($cascade) {
2. ...
3. $rating = $this->read('rating'); // gets the rating of the record being deleted.
4. $name = $this->read('name', $id2); // gets the name of a second record.
5. $rating = $this->read('rating'); // gets the rating of the second record.
6. $this->id = $id3; //
7. $this->read(); // reads a third record
8. $record = $this->data // stores the third record in $record
9. ...
10. }

Notice that the third call to read() fetches the rating of the same record read before. That is because read() changes Model::$id to any value passed as $id. Lines 6-8 demonstrate how read() changes the current model data.