The import/export functions include a powerful function to select data sets, or field contents. You can define the conditions in a language that is very similar to Visual Basic (less powerful, though).
MetaTexis includes an interpreter which interprets the text of the conditions and decides whether the conditions are met or not.
The result of the conditions that you define must be a truth value, that is they must be either true or false. For example, the result of "3 + 3" is not a truth value, but a number. Therefore, it does not have any meaning as a condition for importing or exporting. MetaTexis will interpret such expressions as "true".
Moreover, a condition must contain a variable. If a condition is always true or always false for any data set or field examined, the condition is meaningless. For example, the expression "3 + 3 = 6" is always true. It does not have any meaning for the import/export process.
The only group of variables are the fields or the datasets to be imported/exported. You cannot define your own variables.
You can refer to a field in several ways:
· Name of the field, as displayed in the list of fields of the dialog box concerned, e.g. "Source".
· "Field" or "Field_" + Number of field, as displayed in the list of fields of the dialog box concerned, e.g. "Field1", "Field_1".
The conditions can be complex, that is, you can combine several conditions with the functions "And" and "Or", and you can use brackets.
Here are some examples for a correct condition:
· Example 1:
Field_1 Incl "John"
· Example 2:
Translation Incl "Johannes"
· Example 3:
Field_1 Incl "John" And Translation Incl "Johannes"
· Example 4:
Field_1 Incl "John" And (Translation Incl "Johannes" or Field3 = "Maria")