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DbStruct Function

X#
Create an array containing the structure of a database file.

Namespace:  XSharp.RT
Assembly:  XSharp.RT (in XSharp.RT.dll) Version: 2.21
Syntax
 FUNCTION DbStruct() AS ARRAY
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Return Value

Type: Array
The structure of the 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:
ConstantDescription
DBS_NAMEReturns the name of the field.
DBS_TYPEReturns the data type of the field.
DBS_LENReturns the length of the field.
DBS_DECReturns the number of decimal places for the field.
DBS_ALIAScAlias
If there is no database file in use in the work area, DBStruct() will generate a runtime error.
Remarks
DBStruct() 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, this function operates on the currently selected work area.
It can be made to operate on an unselected work area by specifying it within an aliased expression
Examples
This example opens two database files, then creates an array containing the database structure using DBStruct() within an aliased expression.
The field attributes are then listed using AEval():
X#
1LOCAL aStruct
2USE customer NEW
3USE invoices NEW
4aStruct := Customer->DBStruct()
5AEval(aStruct, {|aField|QOut(aField[DBS_NAME]),;
6QOut(aField[DBS_TYPE]), QOut(aField[DBS_LEN]),;
7QOut(aField[DBS_DEC]), QOut(aField[DBS_ALIAS])})
See Also