Rules and guidelines for search and replace operations
When you configure a step to remove or replace values in an input data field, you can enter the values as properties on the step. You can also use a dictionary to specify the values.
The combination of dictionary values and custom values that you select and the order in which you select them can affect the search and replace operations at run time.
Consider the following rules and guidelines when you configure the properties on a step:
Searching in single-value and multi-value strings
•A search operation looks for complete values in an input field. The search operation ignores any value that occurs within a larger string. For example, a search operation will ignore the value DATA in the string METADATA.
•In a step to remove or replace values, the search operation applies the scope criterion that you select to the values in the input field. The search option does not reapply the scope as the operation progresses.
For example, if you enter the values HARD and DISK as separate search terms in a step and you set the scope to Start, the search operation removes HARD from the string HARD DISK DRIVE. The value DISK remains at the start of the output string.
If you set the scope to Anywhere in the same step, the search operation will remove both HARD and DISK from the input field.
•You can remove or replace more than one value in a string. For example, you can configure a step to remove the values VIRTUAL PRIVATE from VIRTUAL PRIVATE NETWORK.
Selecting the valid column in a dictionary
•When you configure a step to remove dictionary terms, the search operation ignores the terms in the valid column that you select.
You can use a dictionary that contains a single column of data to remove values or to replace data values with a custom value. To do so, select any other column number on the Valid Column field as the valid column.
•You can use a dictionary to find values in the input data and to replace the values with values from the valid column in the dictionary. When you use a dictionary to find and replace values, select a dictionary that contains at least two columns.
•You can review the dictionary data in the Step properties pane and select the valid column that you need.
Differences in search criteria for dictionaries and custom strings
•When you configure a step to remove or replace a list of custom strings, the search operation searches for the strings in the order in which you enter them in the Step properties pane.
For example, let's say that you first enter SITE and then enter WEB SITE as custom strings, and you set the scope to Anywhere. The search operation removes or replaces the value SITE first and cannot subsequently remove the string WEB SITE. The value WEB remains in the output data.
If you enter WEB SITE before SITE in the same step, the search operation will remove both terms from the input field.
•When you configure a step to remove or replace a list of dictionary values with a new value, the search operation prioritizes longer strings in the dictionary.
For example, let's say that you select a dictionary that contains the strings SITE and WEB SITE, and you set the scope to Anywhere. The search operation removes or replaces the value WEB SITE and also removes the value SITE.