SPLIT function not supported

[kaklakariada]

Tableau expects a function SPLIT() that behaves like this:

SPLIT("a-b-c", "-", 2)  -> "b"
SPLIT("a-b-c", "-", -2)  -> "b"

Exasol does not support a function like this, so we need to combine functions to simulate SPLIT().

Tableau function definition:

    <function group='string' name='SPLIT' return-type='str'>
      <argument type='str' />
      <argument type='localstr' />
      <argument type='localint' />
    </function>