Specifying fields with IndexFieldNames
From InterBase
Go Up to Working with Tables
IndexFieldNames
is a string list property. To specify a sort order, list each column name to use in the order it should be used, and delimit the names with semicolons. Sorting is by ascending order only.
The following code sets the sort order for PhoneTable
based on LastName
, then FirstName
:
PhoneTable.IndexFieldNames := 'LastName;FirstName';
Examining the field list for an index
When your application uses an index at runtime, it can examine the
IndexFieldCount
property, to determine the number of columns in the index.IndexFields
property, to examine a list of column names that comprise the index.
IndexFields
is a string list containing the column names for the index. The following code fragment illustrates how you might use IndexFieldCount
and IndexFields
to iterate through a list of column names in an application:
var I: Integer; ListOfIndexFields: array[0 to 20} of string; begin with CustomersTable do begin for I := 0 to IndexFieldCount - 1 do ListOfIndexFields[I] := IndexFields[I]; end; end;
Note:
IndexFieldCount
is not valid for a base table opened on an expression index.