The 4th Dimension language and database engine don’t automatically compare values case-sensitively. Instead, upper- and lower-case versions of a letter, and many of their diacritically marked variations, are considered equal. For example, the QUERY command treats the following characters as identical:
  e é E É Ë
It is often helpful that 4th Dimension doesn’t distinguish between case and diacritically distinct characters. This behavior is an obstacle, however, when you need to compare values case-sensitively.

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