DbOrderInfo Function |  |
Return and optionally change information about orders and index files.
Namespace: XSharp.RT
Assembly: XSharp.RT (in XSharp.RT.dll) Version: 2.19
SyntaxRequest Example
View Source
If uNewSetting is not specified, DBOrderInfo() returns the current setting.
If uNewSetting is specified, the previous setting is returned.
Parameters
- kInfoType (Optional)
- Type: Usual
Specifies the type of information.
The constants are listed in the remarks section below. Note, however, that not all constants are supported for all RDDs. - cIndexFile (Optional)
- Type: Usual
The name of an index file, including an optional drive and directory (no extension should be specified).
Use this argument with cOrder to remove ambiguity when there are two or more orders with the same name in different index files.
If cIndexFile is not open by the current process, a runtime error is raised. - uOrder (Optional)
- Type: Usual
The name of the order about which you want to obtain information or a number representing its position in the order list. (For single-order index files, the order name is the eight-letter index file name.)
Using the order name is the preferred method since the position may be difficult to determine using multiple-order index files. Invalid values are ignored.
If no index file or order is specified, the controlling order is assumed. - uNewSetting (Optional)
- Type: Usual
If specified, this parameter is used to change the value of a setting.
The data type (and whether uNewSetting can be specified), depends on the kInfoType constant and is documented in the Remarks section below.
Return Value
Type: UsualIf uNewSetting is not specified, DBOrderInfo() returns the current setting.
If uNewSetting is specified, the previous setting is returned.
Remarks
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
It can be made to operate on an unselected work area by specifying it within an aliased expression
Examples
This example uses DBOI_NAME to save the current controlling order.
After changing to a new controlling order, it uses the saved value to restore the original order:
This example uses aliased expressions to return the default index file extension (using DBOI_INDEXEXT) in two different work areas:
In this example, DBOrderInfo(DBOI_INDEXEXT) checks for the existence of the CUSTOMER index file independent of the RDD linked into the current work area:
This example accesses the key expression of several orders from the same index file:
This example uses DBOrderInfo() as part of a TOTAL ON key expression. Since DBOrderInfo() returns the expression as a string, it is specified using a macro expression to force evaluation of the key expression:
In this example, ALL_CUST.MDX contains three orders named CUACCT, CUNAME, CUZIP.
The DBOI_INDEXNAME constant is used to display the name of the index file using one of its orders:
The following example searches for CUNAME in the order list:
This example retrieves the "for condition" from an order:
After changing to a new controlling order, it uses the saved value to restore the original order:
X#
1USE customer INDEX name, serial NEW 2cOrder := DBOrderInfo(DBOI_NAME) // name 3Customer->DBSetOrder("serial") 4? DBOrderInfo(DBOI_NAME) // serial 5Customer->DBSetOrder(cOrder) 6? DBOrderInfo(DBOI_NAME) // name
X#
1USE sales INDEX all_sales VIA "DBFCDX" NEW 2USE customer INDEX name, serial VIA "DBFNTX" NEW 3? Sales->DBOrderInfo(DBOI_INDEXEXT) // .CDX 4? Customer->DBOrderInfo(DBOI_INDEXEXT) // .NTX
X#
1USE customer NEW 2IF !File("customer" + DBOrderInfo(DBOI_INDEXEXT)) 3 Customer->DBCreateIndex("customer", "CustName",; 4 {|| Customer->CustName}) 5ENDIF
X#
1USE customer INDEX all_cust VIA "DBFMDX" NEW 2Customer->DBSetOrder("serial") 3? DBOrderInfo(DBOI_EXPRESSION,, "name") 4// Result: key expression for name order 5? DBOrderInfo(DBOI_EXPRESSION,, "serial") 6// Result: key expression for serial order
X#
1USE sales INDEX salesman NEW 2TOTAL ON &(DBOrderInfo(DBOI_EXPRESSION)) ; 3 FIELDS SaleAmount TO summary
The DBOI_INDEXNAME constant is used to display the name of the index file using one of its orders:
X#
1USE customer VIA "DBFNTX" NEW 2Customer->DBSetIndex("all_cust") 3? DBOrderInfo(DBOI_INDEXNAME,, "cuname") 4// Returns: all_cust
X#
1USE customer VIA "DBFNTX" NEW 2Customer->DBSetIndex("cuacct") 3Customer->DBSetIndex("cuname") 4Customer->DBSetIndex("cuzip") 5? DBOrderInfo(DBOI_NUMBER,, "cuname") // 2
X#
1USE customer NEW 2INDEX ON Customer->Acct TO customer ; 3 FOR Customer->Acct > "AZZZZZ" 4? DBOrderInfo(DBOI_CONDITION,, "customer") 5// Returns: Customer->Acct > "AZZZZZ"
See Also