Record Locking - Revision history

Laura: /* Enhancements */

2013-07-15T19:43:39Z

Enhancements

← Older revision		Revision as of 19:43, 15 July 2013
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	<noinclude>		<noinclude>
	[[Category:Needs Help]]		[[Category:Needs Help]]
			[[Category:File Operations]]
	</noinclude>		</noinclude>

Laura at 16:18, 13 July 2013

2013-07-13T16:18:42Z

← Older revision		Revision as of 16:18, 13 July 2013
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	OPTION 33 { 30 \| 31 \| 32 \| 64 } (default is 31)		OPTION 33 { 30 \| 31 \| 32 \| 64 } (default is 31)

	Option 30, or 230 provides for 230 or 1GB (1,073,741,824) maximum bytes in a data file.		Option 30, or 230 provides for 230 or 1GB (1,073,741,824) maximum bytes in a data file.<br>
	Option 31, or 231 provides for 231 or 2GB (2,147,483,648) maximum bytes in a data file.		Option 31, or 231 provides for 231 or 2GB (2,147,483,648) maximum bytes in a data file.<br>
	Option 32, or 232 provides for 231 or 4GB (4,294,967,296) maximum bytes in a data file.		Option 32, or 232 provides for 231 or 4GB (4,294,967,296) maximum bytes in a data file.<br>
	Option 64, or 264 provides for 231 or 17,179,869,184GB [[18 Quintillion]] (18,446,744,073,709,551,616) maximum bytes in a data file.		Option 64, or 264 provides for 231 or 17,179,869,184GB [[18 Quintillion]] (18,446,744,073,709,551,616) maximum bytes in a data file.

Laura at 16:17, 13 July 2013

2013-07-13T16:17:21Z

@@ Line 1: / Line 1: @@
-BR 3.8 uses 31 bit locking. BR 3.9  used 30 bit locking to be compatible with CIFS / SMB products like Samba and SCO Vision. However this proved to be an unacceptable limitation because files that are greater than 1 gigabyte can get random locked records for no apparent reason.
+For '''Record Locking''' [[Business Rules!]] uses a "Virtual Record" to lock individual records.  Instead of locking the actual bytes of a record, it locks a single byte in an area that is unused by the file.
-As of release levels 3.92i/4.02i/4.12i, 31 bit locking is the default. This will take you to approx 1.8 GB without locking conflicts.
+BR [[3.8]] & Prior used 31 bit '''record locking'''.   This provided for 2**31 or [[2,147,483,648]] [[maximum]] bytes in a data file.
-bit locking gives access to about 3.6 GB.
+In both cases, BR used a "Virtual Byte" Starting at around 1 gigabyte.
-Release 4.03 or 4.13 is required to go to 64 bit locking, although this is not possible on Windows 95, 98 and ME.
+ Instead of locking record 1, record 1,000,000,001 was locked.
-In versions 4.0 and above, the new OPTION statement is provided to specify the
+This allowed for [[73,741,824]] records to be locked when using 30 bit record locking.
-OPTION 33 ( 30 / 31 / 32 / 64 ) (the default is 31):
+The problem with this theory is that in both 30 & 31 bit record locking, real live records used the 1GB section of the file for large files.   As a file grew to be very large, there was a section between 1,000,000,001 and 1,073,741,824 that was used by both the virtual locks and the actual records.
-bit support is for compatibility with CIFS (e.g. Samba) when needed.
-bit locking allows for data files up to about 1.8 gig depending on record size. The larger the record size, the higher the boundary.
+This caused a very strange ERROR [[4233]] where locking a record on 1 [[workstation]], would cause an error reading an available record on another workstation.
-and 64 bit locking only work on NT/W2K/XP systems. 32 bits support files up to approx 3.6 gig. 32 and 64 bit support is currently only available in releases 4.03 and 4.13.+
 ;Other Notes:

Laura at 22:43, 20 February 2013

2013-02-20T22:43:00Z

← Older revision		Revision as of 22:43, 20 February 2013
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	without actually locking records. This allows report writers and ODBC to access		without actually locking records. This allows report writers and ODBC to access
	locked records without interference.		locked records without interference.

			<noinclude>
			[[Category:Needs Help]]
			</noinclude>

Laura: Created page with "BR 3.8 uses 31 bit locking. BR 3.9 used 30 bit locking to be compatible with CIFS / SMB products like Samba and SCO Vision. However this proved to be an unacceptable limitati..."

2013-02-20T22:40:09Z

Created page with "BR 3.8 uses 31 bit locking. BR 3.9 used 30 bit locking to be compatible with CIFS / SMB products like Samba and SCO Vision. However this proved to be an unacceptable limitati..."

New page

BR 3.8 uses 31 bit locking. BR 3.9 used 30 bit locking to be compatible with CIFS / SMB products like Samba and SCO Vision. However this proved to be an unacceptable limitation because files that are greater than 1 gigabyte can get random locked records for no apparent reason.

As of release levels 3.92i/4.02i/4.12i, 31 bit locking is the default. This will take you to approx 1.8 GB without locking conflicts.

32 bit locking gives access to about 3.6 GB.

Release 4.03 or 4.13 is required to go to 64 bit locking, although this is not possible on Windows 95, 98 and ME.

In versions 4.0 and above, the new OPTION statement is provided to specify the
number of bits to be used for locking:

OPTION 33 ( 30 / 31 / 32 / 64 ) (the default is 31):
30 bit support is for compatibility with CIFS (e.g. Samba) when needed.
31 bit locking allows for data files up to about 1.8 gig depending on record size. The larger the record size, the higher the boundary.
32 and 64 bit locking only work on NT/W2K/XP systems. 32 bits support files up to approx 3.6 gig. 32 and 64 bit support is currently only available in releases 4.03 and 4.13.+

;Other Notes:
*Large file support on Unix/Linux is currently being researched.
*BR will not start two sessions using different lock bit requirements, and a message box is produced when that is attempted.
*The record locking mechanism was substantially revised to enable record locking
without actually locking records. This allows report writers and ODBC to access
locked records without interference.

← Older revision		Revision as of 16:18, 13 July 2013
Line 24:		Line 24:
	OPTION 33 { 30 \| 31 \| 32 \| 64 } (default is 31)		OPTION 33 { 30 \| 31 \| 32 \| 64 } (default is 31)

	Option 30, or 230 provides for 230 or 1GB (1,073,741,824) maximum bytes in a data file.		Option 30, or 230 provides for 230 or 1GB (1,073,741,824) maximum bytes in a data file.<br>
	Option 31, or 231 provides for 231 or 2GB (2,147,483,648) maximum bytes in a data file.		Option 31, or 231 provides for 231 or 2GB (2,147,483,648) maximum bytes in a data file.<br>
	Option 32, or 232 provides for 231 or 4GB (4,294,967,296) maximum bytes in a data file.		Option 32, or 232 provides for 231 or 4GB (4,294,967,296) maximum bytes in a data file.<br>
	Option 64, or 264 provides for 231 or 17,179,869,184GB [[18 Quintillion]] (18,446,744,073,709,551,616) maximum bytes in a data file.		Option 64, or 264 provides for 231 or 17,179,869,184GB [[18 Quintillion]] (18,446,744,073,709,551,616) maximum bytes in a data file.