The following section describes the syntax and usage of the MID function in ActivityInfo.


The MID function is used to return a specified number of characters from the middle of a string (or text value).


MID(string, numChars, startPosition)

Argument Required Description
string Yes The text value. 
numChars Yes The number of characters you wish to return from the text value.

This must be a numeric value.
startPosition Yes The starting position of the text you wish to extract. The start position is measured from 0 (i.e. the first character in a string is 0, the second 2, etc.)

This must be a numeric value.


  • The sub-string extracted from the middle of the text value, starting at startPosition, which has a length of numChars.
  • NA if the string is empty, not a text value, or if the number of characters requested exceeds the length of the original text.


We will be using the MID function to extract text from the middle of a text field. 


We will be using one Text field:

  • "Text Field" (with code "text")

We will attempt to extract 3 characters from the middle of the field, after the 2nd character in the text.


MID(text, 3, 2)