When you import data into Analytics, or connect to data with Analytics, you need to structure the raw data in order to read it, and perform analysis on it. The structuring device in Analytics is called a table layout. Analytics automatically generates a table layout for every table in an Analytics project.
A table layout is a collection of metadata that describes and defines the raw data in the source data file or source location. Without a table layout, source data would appear like a mass of undifferentiated numbers and letters. The table layout imposes order.
The metadata elements in a table layout
A table layout specifies a number of metadata elements, including:
- names field names – both physical field names, and display names of corresponding columns in views
- types data category and data type of fields
- physical characteristics starting position and byte length of fields
- format format details such as the number of decimal places in numeric fields, and the date format in datetime fields
- connection the location of the source data
How table layouts relate to Analytics tables
The diagram below illustrates the table layout in relation to the other components of an Analytics table.
For more information about how table layouts relate to Analytics tables generally, see The structure of Analytics tables.
Table layout and source data file
The table layout for the Metaphor_Trans_All table, from the ACL_Demo.acl sample data project, appears below, followed by the associated source data file, Metaphor_Trans_All.fil.
You can clearly see how the table layout organizes the source data, and defines a number of fields.
Table layout
Source data file
Table Layout dialog box
You use the Table Layout dialog box (shown above) to define and modify table layouts. You can access the dialog box at any time by selecting Edit > Table Layout. The dialog box includes three tabs for working with particular aspects of the table layout:
| Tab | Description |
|---|---|
| Table Layout Options | Use this tab to configure general properties for the table layout, such as the record length, the data source associated with the table layout, and to add notes about the table layout. |
| Edit Fields/Expressions | Use this tab to create, modify, or delete fields from the table layout. You can work with both physical data fields and computed fields. |
| Add a New Data Filter |
Use this tab to define data filters, which are rules that specify which data from the data source to include or exclude from the record you are defining. Data filters in a table layout are different than filters in Analytics views, and are typically only necessary when you are unsuccessful in defining a data source using the options available in the Data Definition Wizard. |
