Do not flush data

Syntax

Do not flush data

Description

This command causes all data file operations to be carried out without writing the changed data to disk at each Update files or Delete. The command is designed to speed up data file operations when the user is prepared to take the extra risk of data loss.

The command operates best when there is a single user logged into the data file. It is unlikely to cause speed increase if the data is on a network volume (that is, shared by several users).

If you use Test for only one user at the beginning of the method, further users are prevented from opening the data file until the method terminates.

The command sets the flag if the state of the 'Do not flush data' mode is changed. When placed in a reversible block, the command restores the previous state of the 'Do not flush' flag upon the termination of the method.

Example

# fast import
Test for only one user 
If flag true 
  Do not flush data 
  Drop indexes 
End If 

Prompt for import file 
Prepare for import from file {Delimited(tabs)}
Import data lImportList
End import 
Close import file 

For each line in list from  1 to  lImportList.$linecount step  1
  Prepare for insert ## transfer list to file
  Load from list 
  Update files 
End For 
Flush data now ## writes the data immediately to disk
Build indexes ## rebuild indexes
Flush data ## Changes mode back to 'Flush data'