Case Sensitivity

By default, Maintain does not usually distinguish between uppercase and lowercase letters. You can enter keywords and names (such as data source and field names) in any combination of uppercase and lowercase letters. The only two exceptions are the MAINTAIN and END keywords used to begin and end a request. These keywords must be uppercase.

However, if mixed-case or NLS field and segment names are used in your application by enabling the MNTCON MATCH_CASE command, you must be consistent with the case style used in the names you give your variables and other application components. In addition, function names must match exactly as written in the documentation. However, Maintain keywords, such as Repeat and Include, do not need any special consideration when using this feature. For more information on MNTCON MATCH_CASE, see MNTCON MATCH_CASE.

For example, the following ways of specifying the REPEAT command are equally valid, and Maintain always considers them to be identical:


By default, you can mix uppercase and lowercase to make variable names more understandable to a reader. For example, the stack name SALARYSTACK could also be represented as SalaryStack.

You may notice that when this manual presents sample Maintain source code, it shows keywords in uppercase, and user-defined names (such as field and stack names) in mixed case. This is only a documentation convention, not a Maintain language rule. As already explained, you can code Maintain commands in uppercase and lowercase.

While, by default, Maintain is not sensitive to the case of syntax, it is sensitive to the case of data. For example, the MATCH command distinguishes between the values SMITH and Smith.

Note: Any Master Files that Maintain accesses must have field and segment names in uppercase unless the MATCH_CASE feature is enabled.