UPDATE (XFILE)

9.0D

The UPDATE instruction allows a record to be partially or completely updated in place. The statement format is as follows:

Where:

label

Optional. A Program Execution Label.

xfile

Required. A previously defined and opened XFILE variable in which data is updated.

field

Optional. The name of a field.

var

Optional. A previously defined Character String Variable, Numeric Variable, string or numeric ARRAY, or individual array element.

listctl

Optional. A supported list control.

;

Optional. indicates Partial I/O.

Flags Affected: OVER

Note the following:

1. This instruction modifies the record associated with the last successful READ, WRITE, or REPOSIT operation.

2. If the current file position is invalid, an I/O error occurs.

3. {field} is an identifier for the field to the updated from the {var} variable. The syntax for {field} can be one of the following:

 

field name

$field name

@{svar} where {svar} is a variable that contains the field name

 

4. If a $ precedes the field name, the $ character is stripped off and the field name references an attribute field.

5. If no $ character precedes the field name, the field name references an element field or an attribute field.

6. If no {field} is specified, the name of the {var} variable is the field name.

7. No support for updating recordsets is available through update. The recordset must be access through a READ statement and modified using the other I/O statements.

8. The supported {listctl} controls are as follows:

 

Control	Function
*LC	Data is written in the case in which it was stored
*LL	Set the Length Pointer to last non-blank character
*PL	Disable *LL (default)
*UC	Convert lower-case data to upper-case
*ZF	Zero-fill numeric variables
*ZS	Blank-fill zero numeric variables

 

9. Using a semicolon (;) as a terminator for partial I/O has no effect.

See Also: XML Support