Forces the operating system of the computer where the data files are found to write data onto the disk. The HFSQL context of the data file used is stored (lock, current browse, ...).
Remark: Used on a regular basis, this function minimizes the loss of data caused by the unexpected system outage on the computer where the data files are located (power failure for example).
// Add a record in a data file
// (record described through programming)
Customer.LastName = "Clark"
Customer.FirstName = "Vince"
Customer.Address = "Palm lane"
Customer.City = "San Francisco"
Customer.Zip = "94102"
Customer.Country = "USA"
HAdd(Customer)
// Forces a write operation into Customer file
HFlush(Customer)
Syntax
<Data file>: Character string
Name of the data file used.
If this name is not specified, HFlush will use the last data file used by the last HFSQL function (function starting with "H").
If this parameter corresponds to "*", HFlush will be applied to all open data files.
Caution: In this case, the execution of function can be quite long.
This parameter can also correspond to the name of a group of files (or custom-folder) defined in the analysis (not available in Android and Android widget).
Remarks
HSecurity and HFlush
HSecurity and
HFlush can both be used to force a physical write operation on disk.
However:
- HSecurity is used to force a write operation into the data files used during each write operation. This write operation is automatically performed by the HFSQL engine. The data files used are not closed during this write operation. The speed of the write-to-file operation is slower.
- HFlush forces the data file(s) to be written when it is called. The data files used are closed then re-opened during this write operation. The speed of the write-to-file operation is not slowed down.