DbStruct Function (Usual) | |
Create an array containing the structure of a database file.
Namespace:
XSharp.RT
Assembly:
XSharp.RT (in XSharp.RT.dll) Version: 2.19
Syntax FUNCTION DbStruct(
uArea AS USUAL
) AS ARRAY
public static Array DbStruct(
Usual uArea
)
Request Example
View SourceParameters
- uArea
- Type: Usual
Specifies the work area name or number for a table from which the value must be retrieved.
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:
Constant Attribute
DBS_NAME cName
DBS_TYPE cType
DBS_LEN nLength
DBS_DEC nDecimals
DBS_ALIAS cAlias
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():
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