SYS(2021) - Filtered Index Expression

Returns the filter expression for an open single-entry index (.idx) file or filter expressions for tags in compound index (.cdx) files.

SYS(2021, nIndexNumber [, nWorkArea | cTableAlias])

Parameters

nIndexNumber

The numeric expression nIndexNumber specifies which filter expression to return from the open index files. SYS(2021) returns filter expressions from open index files in the following order as nIndexNumber increases from 1 to the total number of open single-entry .idx files and structural compound and independent compound index tags:

  1. Filter expressions from single-entry .idx files (if any are open) are returned first. The order in which the single-entry .idx files are included in USE or SET INDEX determines the order in which the filter expressions are returned.

  2. Filter expressions for each tag in the structural .cdx file (if one is present) are returned next. The filter expressions are returned from the tags in the order the tags were created in the structural index.

  3. Filter expressions for each tag in any open independent .cdx files are returned last. The filter expressions are returned from the tags in the order the tags were created in the independent compound indexes.

The empty string is returned if nIndexNumber is greater than the total number of open single-entry .idx files and structural and independent .Cdx file tags.

nWorkArea

Specifies the work area number for a table open in another work area.

cTableAlias

Specifies a table alias for a table open in another work area. If a table doesn't have the alias you specify, Visual FoxPro displays an error message.

Expand imageReturn Value

Expand imageRemarks

Expand imageSee Also


© , 1996-2020 • Updated: 11/10/20
Comment or report problem with topic