## Read

You can get any information out of a Data Master, Data Grid or Data List in order to use it for other calculations or just to display it separately using event actions.

Reading entire record's instances

To get a specific Data Master's record instance or a collection of them use one of the following data sources in the Expression Builder:

- Data Master: Represents the collection of all the Data Master's instances.

- Data List: Represents the collection of all the Data Master's instances currently displayed by the Data List.

- Data List's row: Represents the instance displayed by the current row.

- Data Grid: Represents the collection of all the Data Master's instances currently displayed by the Data Grid..

- Data Grid's cell: Represents the instance displayed by the current cell.

- Variable: Container of any of the mentioned data types above.

Additionally you can filter any of the data sources mentioned above in order to get a more specific record instance. To do so, you will need to create a Filter expression in the Expression Builder dialog.

Reading record instance's fields

To get a specific field from a Data Master's record instance in the Expression Builder you will have to use the Select function. The Select function needs two parameters:

- First parameter: Introduce here a Data Master's record instance or a collection of instances. To do so, you can drag and drop any Data Master, Data List, Data List's row, Data Grid, Data Grid's cell or Variable containing record instances.

- Second parameter: Introduce here the Data Master's field you want to get from the instances' collection.

If the first parameter defines a collection of record instances, then the select operation will return a list of values:

If the first parameter defines a single record instance, then the select operation will return a single value:

For further information check out the video tutorial: http://www.justinmind.com/tutorials/advanced-level/edit-forms/