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DBSTRUCT()
Create an array containing the structure of a database file
------------------------------------------------------------------------------
Syntax
DBSTRUCT() --> aStruct
Returns
DBSTRUCT() returns the structure of the current database file in an
array whose length is equal to the number of fields in the database
file. Each element of the array is a subarray containing information
for one field. The subarrays have the following format:
DBSTRUCT() Return Array
------------------------------------------------------------------------
Position Metasymbol Dbstruct.ch
------------------------------------------------------------------------
1 cName DBS_NAME
2 cType DBS_TYPE
3 nLength DBS_LEN
4 nDecimals DBS_DEC
------------------------------------------------------------------------
If there is no database file in USE in the current work area, DBSTRUCT()
returns an empty array ({}).
Description
DBSTRUCT() is a database function that operates like COPY STRUCTURE
EXTENDED by creating an array of structure information rather than a
database file of structure information. There is another function,
DBCREATE(), that can create a database file from the structure array.
By default, DBSTRUCT() operates on the currently selected work area. It
will operate on an unselected work area if you specify it as part of an
aliased expression as shown below.
Note, a header file, Dbstruct.ch, located in \CLIP53\INCLUDE contains a
series of manifest constants for each field attribute.
Examples
. This example opens two database files and then creates an
array containing the database structure using DBSTRUCT() within an
aliased expression. The field names are then listed using AEVAL():
#include "Dbstruct.ch"
//
LOCAL aStruct
USE Customer NEW
USE Invoices NEW
//
aStruct := Customer->(DBSTRUCT())
AEVAL( aStruct, {|aField| QOUT(aField[DBS_NAME])} )
Files Library is CLIPPER.LIB, header file is Dbstruct.ch.
See Also:
AFIELDS()*
COPY STRU EXTE
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