Module CompoundDescriptors

gets possible descriptor names from a database

**Arguments**

  - db: the name of the database to use

  - tbl1: the name of the table to be used for reading descriptor values

  - tbl2: the name of the table to be used for reading notes about the
    descriptors (*descriptions of the descriptors if you like*)

  - user: the user name for DB access

  - password: the password for DB access

**Returns**

  a 2-tuple containing:

    1) a list of column names

    2) a list of column descriptors

**Notes**

  - this uses _Dbase.DbInfo_  and Dfunctionality for querying the database

  - it is assumed that tbl2 includes 'property' and 'notes' columns

countOptions

Value:

[('NVAL', 'total number of valence electrons'), ('NVAL_NO_FULL_F', 'nu mber of valence electrons neglecting filled f shells'), ('NVAL_NO_FULL _D', 'number of valence electrons neglecting filled d shells'), ('NVAL _NO_FULL', 'number of valence electrons neglecting filled f and d shel ls')]