Working with Strings

There are a number of operations available for strings, including:

  • Converting a string to upper case or lower case—uppertolower(CHAR).
  • Removing specified characters, such as `ID_` or `$`, from a string variable—stripchar(CHAR,STRING).
  • Determining the length (number of characters) for a string variable—length(STRING).
  • Checking the alphabetical ordering of string values—alphabefore(STRING1, STRING2).
  • Removing leading or trailing white space from values—trim(STRING), trim_start(STRING), or trimend(STRING).
  • Extract the first or last n characters from a string—startstring(LENGTH, STRING) or endstring(LENGTH, STRING). For example, suppose you have a field named item that combines a product name with a four-digit ID code (ACME CAMERA-D109). To create a new field that contains only the four-digit code, specify the following formula in a Derive node:
    endstring(4, item)
  • Matching a specific pattern—STRING matches PATTERN. For example, to select persons with "market" anywhere in their job title, you could specify the following in a Select node:
    job_title matches "*market*"
  • Replacing all instances of a substring within a string—replace(SUBSTRING, NEWSUBSTRING, STRING). For example, to replace all instances of an unsupported character, such as a vertical pipe ( | ), with a semicolon prior to text mining, use the replace function in a Filler node. Under Fill in fields:, select all fields where the character may occur. For the Replace: condition, select Always, and specify the following condition under Replace with:
    replace('|',';',@FIELD)
  • Deriving a flag field based on the presence of a specific substring. For example, you could use a string function in a Derive node to generate a separate flag field for each response with an expression such as:
hassubstring(museums,"museum_of_design")

See the topic String Functions for more information.