When you import data into a data object, the system generates a .csv file if any errors occur during the import process. The .csv file contains error details for the records for each row in the file. After reviewing the file, you can fix the errors and re-import the data. You can also change the location to which the system writes the .csv file. For example, for a multi-node system, you can set the destination to a shared location so that users can access the file from any node in the system. For more information, see Changing the storage destination for the import data wizard, BIX, and file listeners.

The following issues can arise when you import data into your data model:

It is possible for a record to pass the validation step and still have an error that the system only detects during the actual import process. This can occur when the schema for externally mapped tables has restrictions that are not known in the rules, for example, if the length specified for a text column does not match the length in the property rule. Records without errors are still imported, but performance might be affected and the error messages might be confusing because they will be generated by the database.

• To ensure that this situation does not occur, ensure that the property definitions match the table columns as closely as possible, or use a validate rule that enforces the same restrictions as the schema.

If the Current import statistics section of the Validate and review screen of the Data Import wizard displays errors, resolve them by completing the following steps:

1. Click Download.
2. Follow the instructions in the .csv file to fix the rows that have errors.
3. Close the Import progress dialog box, and then retry the import process with your updated file.
   Note: If you proceed with the import process despite the errors, the system only imports rows without errors.

When data for a data object is imported, the date time formats in the import file must be a supported format or the import fails. The Data Import wizard supports several categories of date time formats to which it attempts to match the incoming date time format. The Data Import wizard stops looking for a match when the wizard finds a matching date time format. Ensure that the date-time fields match one of the following formats:

• If you enter a custom date time format in the Data Import wizard, the Data Import wizard uses the custom format and does not look for a match in the other date time categories.
• An extension point format. Data page or data transform that uses the Pega-supplied D_pyCustomDateFormats data page as its source. The extension point supports Pega-supplied formats and simple date formats. The record editor class is Data-Metadata-CustomDateFormat.
• Use ISO-8601 universal formats, which are not locale-specific.
  For example: yyyy-MM-dd HH:mm:ss
• Locale-specific. The default Microsoft Excel date time formats for the user's locale, for locales supported by Pega Platform. For formats not supported by Pega Platform, the system uses the default Microsoft Excel format for the United States locale. For a list of supported locales and their formats, see Locale settings - date time formats. For information about Microsoft Excel date time formats, refer to the Microsoft Excel documentation.
  For example: yyyyMMdd'T'HHmmss.SSS 'GMT', which is the Pega ISO format (Pega default format)