MyDAC

TMemDataSet.IndexFieldNames Property

Used to get or set the list of fields on which the recordset is sorted.

Class

TMemDataSet

Syntax

property IndexFieldNames: string;

Remarks

Use the IndexFieldNames property to get or set the list of fields on which the recordset is sorted. Specify the name of each column in IndexFieldNames to use as an index for a table. Ordering of column names is significant. Separate names with semicolon. The specified columns don't need to be indexed. Set IndexFieldNames to an empty string to reset the recordset to the sort order originally used when the recordset's data was first retrieved.

Each field may optionally be followed by the keyword ASC / DESC or CIS / CS / BIN.

Use ASC, DESC keywords to specify a sort direction for the field. If one of these keywords is not used, the default sort direction for the field is ascending.

Use CIS, CS or BIN keywords to specify a sort type for string fields:

CIS - compare without case sensitivity;

CS - compare with case sensitivity;

BIN - compare by character ordinal values (this comparison is also case sensitive).

If a dataset uses a TCustomDAConnection component, the default value of sort type depends on the TCustomDAConnection.Options option of the connection. If a dataset does not use a connection (TVirtualTable dataset), the default is CS.

Read IndexFieldNames to determine the field (or fields) on which the recordset is sorted.

Ordering is processed locally.

Note: You cannot process ordering by BLOB fields.

Example

The following procedure illustrates how to set IndexFieldNames in response to a button click:

DataSet1.IndexFieldNames := 'LastName ASC CIS; DateDue DESC'; 
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