AMPscript provides the ability to split strings into arrays (or lists), making it easier to process individual components of a string. The primary function used to split strings in AMPscript is BuildRowsetFromString(). This function splits a string based on a specified delimiter and stores the resulting substrings in a rowset (which is essentially a collection of values).

1. Using BuildRowsetFromString()

The BuildRowsetFromString() function is used to split a string into individual components based on a delimiter and returns a rowset. You can then loop through this rowset to extract each individual value.

Syntax:

BuildRowsetFromString(string, delimiter)

• string: The string to be split.
• delimiter: The character or characters used to split the string.

Example: Split a Comma-Separated List

%%[

  SET @string = “apple,banana,orange,grape”

  SET @rowset = BuildRowsetFromString(@string, “,”)

  SET @rowCount = RowCount(@rowset)

  FOR @i = 1 TO @rowCount DO

    SET @item = Field(Row(@rowset, @i), 1)

    OUTPUTLINE(@item)

  NEXT @i

]%%

Explanation:

• The string “apple,banana,orange,grape” is split into individual items using a comma , as the delimiter.
• The Rowset contains each item, and the FOR loop iterates through the rowset to output the individual items (apple, banana, orange, grape).

2. Using Field() to Access Elements

Once you have split the string into a rowset, you can access individual elements using the Field() function by specifying the row and column. Since the rowset is 1-based, the first element is accessed using Row(@rowset, 1).

Example: Access a Specific Element from the Split String

%%[

  SET @string = “apple,banana,orange,grape”

  SET @rowset = BuildRowsetFromString(@string, “,”)

  SET @secondItem = Field(Row(@rowset, 2), 1)

  OUTPUTLINE(“The second item is: ” & @secondItem)

]%%

Explanation:

• The string is split, and the second item (banana) is extracted using Row(@rowset, 2) and Field(Row(), 1).

3. Handling Edge Cases

If the delimiter is not found or the string is empty, you may need to account for those cases to avoid errors.

Example: Handling Empty or Missing Delimiters

%%[

  SET @string = “”

  SET @rowset = BuildRowsetFromString(@string, “,”)

  SET @rowCount = RowCount(@rowset)

  IF @rowCount > 0 THEN

    SET @firstItem = Field(Row(@rowset, 1), 1)

    OUTPUTLINE(“The first item is: ” & @firstItem)

  ELSE

    OUTPUTLINE(“No items found.”)

  ENDIF

]%%

Explanation:

• The code checks if the rowset contains any items before trying to access the first element.

Use Case Example: Email Personalization with Split Strings

Let’s say you have a Data Extension field containing a list of product interests (e.g., “Shoes,Shirts,Accessories”) and you want to personalize an email with the first product.

Example: Split Product Interests and Personalize Email

%%[

  SET @productInterests = AttributeValue(“ProductInterests”)

  SET @rowset = BuildRowsetFromString(@productInterests, “,”)

  SET @firstProduct = Field(Row(@rowset, 1), 1)

  OUTPUTLINE(“Your first product interest is: ” & @firstProduct)

]%%

Explanation:

• The field ProductInterests is split using a comma as the delimiter, and the first product (Shoes) is extracted and displayed in the email.

5. Important Considerations

• Rowset Indexing: AMPscript rowsets are 1-based (i.e., the first item is at index 1, not 0).
• Delimiter: The delimiter must be a single character, such as a comma, space, or semicolon. You can use multiple characters if necessary (e.g., “; “).
• Null or Empty Values: Ensure that the string is not null or empty before splitting to avoid runtime errors.

Best Practices:

• Use the RowCount() function to check how many items were created after splitting the string to avoid accessing non-existing elements.
• Optimize string splitting for performance by keeping the string size reasonable and limiting unnecessary splits in emails with large subscriber bases.