Getting table values using collections

Question

For my custom payment module I have a database table where I need to retrieve data from, but I have issues using collections. For example I have a column named "order_id", I load the model that I have in my module and get the collection using $model->getCollection(); What's the correct way to get the data now?

When I use $collection->getData()["order_id"], I get an array with fields like ["order_id"]=> string(9) "145000021".

How can I get just the value from the table?

Answer 1

A collection returns a collection/list of all found records/items/rows. It doesn't matter if the result is only with one item. So you have to use foreach to iterate over the collection result, i.e.:

$items = $collection->getData();
foreach ($items as $item) {
    $order_id = $item->getOrderId();
    //do something with $order_id
}

or if you like to get only the first item, you can use directly this:

$order_id = $collection->getFirstItem()->getOrderId();