When you have a Table loaded in the Viewer, you can see the Table Structure by selecting the "Table Structure info" TAB

You have a button to export this structure directly to the Clarion 6 (txd) or Clarion 7 (dctx) formats so as to only have to import those created files in your dictionary (much easier mainly for ODBC Tables then setting up a DSN etc ...)

After exporting the structure DMC will automatically open the relevant folder for you to use the created file
Files are placed in the %install_path_data%\cgf_import\structures directory
Files are named with this convention :
txd => "Dmc_TXD_TableName_Struct.txd"
dctx => "Dmc_DCTX_TableName_Struct.dctx"
Clarion 7 accepts both formats for imports
IMPORTANT : Please remember that a Table cannot have the SAME NAME used twice - ie: for a Column and a Key (like in the example on this page "COMPANYNAME" Column and Key).
If this is the case you will have to change the names to be able to import them.