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Stored procedures
HStartLock (Function)
In French: HDébutVerrou
HFSQLHFSQL Client/ServerAvailable only with these kinds of connection
This function is available for backward compatibility (this function will still be available in the forthcoming version).
Caution: Modification since WINDEV 5.5: HAdd, HCross, HModify, HWrite, ... unlock the record.
The documentation about HStartLock available in WINDEV 5.5 is as follows.
Windows Mobile This function can be used with HFSQL Client/Server data files or with data files handled by Native Accesses. This function is not available for HFSQL Mobile.
Note: From version 19, HFSQL is the new name of HyperFileSQL.
 
Purpose
Marking the start of read lock on data files.
Syntax
HStartLock
Details
The records read after HStartLock will be locked.
HRead, HReadSeek, HReadFirst, HReadLast, HReadNext and HReadPrevious read and lock the record (they are equivalent to HReadLock, HReadSeekLock...).
HAdd, HCross, HModify, HWrite... do not unlock the record.
The records will be unlocked during HEndLock.
Notes
  • The end of lock is declared by HEndLock.
  • After HStartLock, to read a record without locking it, you must use HReadNoLock, HReadFirstNoLock, HReadLastNoLock, HReadPreviousNoLock, HReadNextNoLock or HReadSeekNoLock.
  • Locking the data files is useful in semi-custom mode. Indeed, in automatic mode, the data files are locked as soon as they are opened.
  • For each data file, the maximum number of records that can be locked is equal to 16.000. Therefore, you must control the total number of locked records. Above 16.000 locked records, the entire data file must be locked (HLockFile or HLockEntireFile).
  • HStartLock and HEndLock are used to easily transform a single-user program into a program that supports locks.
Minimum required version
  • Version 9
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