Shifting fields in table layouts

Shifting fields allows you to correct field definitions that are displaced by a fixed number of bytes. This is only required if the table layout was incorrectly defined, or if changes have been made to the data source and you do not want to redefine your ACL table. If a data source has minor changes, such as an increased field length for one of the fields you have defined, you can shift the position of the subsequent fields and keep using the updated table layout. By shifting a field’s start position in a table layout, you automatically shift the start positions of all of the fields defined to the right of that field. Shifting fields only affects physical data fields.

When you shift fields in your table layout you may also need to adjust the Record Length value in the Table Layout Options tab if any of the following situations apply:

To shift fields in a table layout:

  1. Select Edit > Table Layout.
  2. Click the Edit Fields/Expressions tab.
  3. If more than one data filter is defined for the table layout, you can choose to shift fields for a particular data filter only. Select the data filter to shift fields for from the drop-down list above the field list table. ACL only displays fields associated with the selected data filter, and these are the only fields the changes will affect.
  4. If you want to start shifting fields from a particular field, you can select the field in the field list table to identify the start of the field as the starting position. By default, the first position in the selected record is used, but you can also enter the position manually in the Shift Fields dialog box.
  5. Click Shift Fields.
  6. In the Shift Fields dialog box, complete the following steps:
    1. Verify the value in the Start Shifting Fields from position text box, or enter a new value.
    2. In Shift fields by the following number of bytes, enter a positive number to shift fields to the right or a negative number to shift fields to the left.

      ACL checks to ensure that the shifted field definitions do not extend past the end of the record, or result in field definitions with negative start values. If either of these situations is identified an error message is displayed.

    3. Click OK.
    4. Click Yes in the Confirm field realignment dialog box.


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