Difference between revisions of "COLUMNMETADATA()"

Revision as of 13:34, 16 February 2016

Purpose

Function to return the METADATA string from the Active Data Dictionary associated with the specified column in the active table

Syntax

COLUMNMETADATA(<expC1>)

See Also

ACLASS(), ADDPROPERTY(), AMEMBERS(), COMPOBJ(), CREATEOBJECT(), DEFINE CLASS, DISPLAY CLASSES, DODEFAULT(), FOREACH, JSON_DECODE(), JSON_DECODE_FILE(), JSON_ENCODE(), LIST CLASSES, LOADOBJECT(), METADATA_DECODE(), METADATA_ENCODE(), METADATA_FINDTYPE(), NEWOBJECT(), OBJECT(), PRINT_JSON(), PRINT_HTML(), PRINT_R(), PRINT_XML(), REMOVEPROPERTY(), REQUIRE_ONCE(), SAVEOBJECT(), SQL SELECT, SOCKET_CLOSE(), SOCKET_LASTERROR(), SOCKET_OPEN(), SOCKET_PEEK(), SOCKET_READ(), SOCKET_SERVER(), SOCKET_WRITE(), TABLEMETADATA(), WITH, XML_DECODE_FILE()

Description

The COLUMNMETADATA() function is used to return the METADATA string from the Active Data Dictionary associated with the specified column in the active table. This can be a JSON encoded complex object containing properties that are arrays of objects or nested objects. You can change the elements of the metadata object then update the Active Data Dictionary with the new metadata.

Example

open database southwind
use customers
omd = object()
omd.caption = "Customer Name"
omd.searchfield = .t.
alter table customers modify constraint companyname metadata json_encode(omd)
use customers
omd = json_decode( columnMetaData("companyname"))
omd.caption = "Customer"
omd.picture = "@!"
omd.searchfield = .t.
alter table customers modify constraint companyname metadata json_encode(omd)
?  json_decode( columnMetaData("companyname"))
 
 
 
Object (refcnt=1)
(
    [caption] => Customer
    [searchfield] => True
    [picture] => @!
)