# Fields tab
The **Fields** tab allows you to define the properties for the fields being exported.
| Column | Description |
| -------------------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| **Name** | Specify the name of the field. |
| **Type** | Select the field's data type from the dropdown list or enter it manually. |
| **Format** | Select the format mask (number type) from the dropdown list or enter it manually. See [Common Formats](/pdia-data-integration/10.2-data-integration/pdi-transformation-steps-reference-overview/common-formats.md) for information on common valid date and numeric formats you can use in this step. |
| **Length** | Specify the length of the field, according to the following field types:
Total number of significant figures in a number.
Total length of string.
Total length of printed output of the string. For example, 4 only returns the year.
|
| **Precision** | Specify the number of floating point digits for number-type fields. |
| **Currency** | Specify the symbol used to represent currencies (for example, `$` or `€`). |
| **Decimal** | Specify the symbol used to represent a decimal point, either a period (`.`) as in `10,000.00` or it can be a comma (`,`) as in `5.000,00`. |
| **Group** | Specify the method used to separate units of thousands in numbers of four digits or larger, either a comma (`,`) as in `10,000.00` or (`.`) as in `5.000,00`. |
| **Trim type** | Select the trimming method (none, left, right, or both) to apply to a string, which truncates the field before processing. Trimming only works when no field length is specified. |
| **Null** | Specify the string to insert into the output text file when the value of the field is null. |
| **Get Fields** (button) | Click to retrieve a list of fields from the input stream. |
| **Minimal width** (button) | Click to minimize the field length by removing unnecessary characters. If selected, string fields will no longer be padded to their specified length. |
See \[Understanding PDI data types and field metadata]\(../../../../Data%20Integration%20Perspective/Data%20Integration%20perspective%20in%20the%20PDI%20client/Advanced%20topics%20(PDI%20perspective)/Understanding%20PDI%20data%20types%20and%20field%20metadata.md) to maximize the efficiency of your transformation and job results.
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