Table B (File architecture) - Revision history

JDamon: /* Structure of a Table B page */

2024-11-15T03:25:28Z

Structure of a Table B page

← Older revision		Revision as of 03:25, 15 November 2024
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	Not shown in the figure above is a 4-byte "Reuse Queue page number" for Unordered files. If it is present, it is in the lower right-hand corner, before working backwards to the first record on the page.		Not shown in the figure above is a 4-byte "Reuse Queue page number" for Unordered files. If it is present, it is in the lower right-hand corner (offset 6140), before working backwards to the first record on the page.

	Each item in the figure is described below.		Each item in the figure is described below.

JDamon: /* Structure of a Table B page */

2024-11-07T20:24:22Z

Structure of a Table B page

← Older revision		Revision as of 20:24, 7 November 2024
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	Not shown in the figure above is a 4-byte "Reuse Queue page number" for Unordered files. If it is present, it is in the lower ~~left~~-hand corner ("before," working backwards, the first record on the page).		Not shown in the figure above is a 4-byte "Reuse Queue page number" for Unordered files. If it is present, it is in the lower right-hand corner, before working backwards to the first record on the page.

	Each item in the figure is described below.		Each item in the figure is described below.

JAL: /* Use in indexing */ link repair

2016-04-22T17:00:34Z

Use in indexing: link repair

← Older revision		Revision as of 17:00, 22 April 2016
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	<ul>		<ul>
	<li>See [[Table C (File architecture)#Segment ~~Entries~~ \|Table C ~~Segment Entries~~]] for the effect of segments in the hash index.		<li>See [[Table C (File architecture)#Segment entries \|Table C segment entries]] for the effect of segments in the hash index.

	<li>See [[Table D (File architecture)#B-~~Tree~~ index structure\|B-~~Tree~~ index structure]] for the effect of segments in the ordered index.		<li>See [[Table D (File architecture)#B-tree index structure\|B-tree index structure]] for the effect of segments in the ordered index.

	<li>See [[Table D (File architecture)#Bitmaps used in indexing\|Bitmaps used in indexing]] for how segments relate to the detailed level of both types of indexes.		<li>See [[Table D (File architecture)#Bitmaps used in indexing\|Bitmaps used in indexing]] for how segments relate to the detailed level of both types of indexes.

Dme at 05:06, 10 May 2014

2014-05-10T05:06:14Z

← Older revision		Revision as of 05:06, 10 May 2014
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	Refer to [[Record (File architecture)\|Record]] and [[Adding records (File architecture)\|Adding records]] for a full discussion of record architecture.		Refer to [[Record (File architecture)\|Record]] and [[Adding records (File architecture)\|Adding records]] for a full discussion of record architecture.

	Refer also to [[~~Record design (File management)\|~~Record design]] for the best use of Model 204 records.		Refer also to [[Record design]] for the best use of Model 204 records.

	===Table B segments===		===Table B segments===

Dme at 04:56, 10 May 2014

2014-05-10T04:56:04Z

← Older revision		Revision as of 04:56, 10 May 2014
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	This page describes the internal architecture of a Model 204 Table B page.		This page describes the internal architecture of a Model 204 Table B page.

	For a discussion of the ways a File Manager can organize these pages in a file, refer to [[~~File design (File management)\|~~File design]].		For a discussion of the ways a File Manager can organize these pages in a file, refer to [[File design]].

	At a minimum, Table B contains all of the base records in a Model 204 file.		At a minimum, Table B contains all of the base records in a Model 204 file.

JAL: /* Parameters related to the use of Table B */

2014-01-29T19:20:15Z

Parameters related to the use of Table B

← Older revision		Revision as of 19:20, 29 January 2014
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	Also not shown are the parameters that control the [[Managing file and table sizes#Automatic increases\|automatic increase]] in table size.</p>		Also not shown are the parameters that control the [[Managing file and table sizes#Automatic increases\|automatic increase]] in table size.</p>

	<table style="Width:80%">		<table class="thJustBold" style="Width:80%">
	<tr><td>[[BHIGHPG parameter\|BHIGHPG]]</td>		<tr><th>[[BHIGHPG parameter\|BHIGHPG]]</th>
	<td>Table B highest active page. Normally the high water mark of pages used (except for Hash Key and Sorted files). Viewable only. </td></tr>		<td>Table B highest active page. Normally the high water mark of pages used (except for Hash Key and Sorted files). Viewable only. </td></tr>

	<tr><td>[[BQLEN parameter\|BQLEN]]</td>		<tr><th>[[BQLEN parameter\|BQLEN]]</th>
	<td>The number of pages in the reuse queue. Viewable only. </td></tr>		<td>The number of pages in the reuse queue. Viewable only. </td></tr>

	<tr><td>[[BRECPPG parameter\|BRECPPG]]</td>		<tr><th>[[BRECPPG parameter\|BRECPPG]]</th>
	<td>The maximum number of record slots on a Table B page. </td></tr>		<td>The maximum number of record slots on a Table B page. </td></tr>

	<tr><td>[[BRESERVE parameter\|BRESERVE]]</td>		<tr><th>[[BRESERVE parameter\|BRESERVE]]</th>
	<td>Table B Reserved space. </td></tr>		<td>Table B Reserved space. </td></tr>

	<tr><td>[[BREUSE parameter\|BREUSE]]</td>		<tr><th>[[BREUSE parameter\|BREUSE]]</th>
	<td>The minimum percentage of free space necessary to add a page to the reuse queue, over and above BRESERVE. </td></tr>		<td>The minimum percentage of free space necessary to add a page to the reuse queue, over and above BRESERVE. </td></tr>

	<tr><td>[[BREUSED parameter\|BREUSED]]</td>		<tr><th>[[BREUSED parameter\|BREUSED]]</th>
	<td>The numberof record slots reused. </td></tr>		<td>The numberof record slots reused. </td></tr>

	<tr><td>[[BRLIMSZ parameter\|BRLIMSZ]]</td>		<tr><th>[[BRLIMSZ parameter\|BRLIMSZ]]</th>
	<td>Base record size maximum. Viewable only. </td></tr>		<td>Base record size maximum. Viewable only. </td></tr>

	<tr><td>[[BSIZE parameter\|BSIZE]]</td>		<tr><th>[[BSIZE parameter\|BSIZE]]</th>
	<td>The number of pages in Table B. </td></tr>		<td>The number of pages in Table B. </td></tr>

	<tr><td nowrap>[[RECRDOPT parameter\|RECRDOPT]]</td>		<tr><th nowrap>[[RECRDOPT parameter\|RECRDOPT]]</th>
	<td>Record storage options. </td></tr>		<td>Record storage options. </td></tr>
	</table>		</table>

	[[Category:File architecture]]		[[Category:File architecture]]

JAL: /* Parameters related to the use of Table B */

2014-01-29T19:16:44Z

Parameters related to the use of Table B

← Older revision		Revision as of 19:16, 29 January 2014
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	<table style="Width:80%">		<table style="Width:80%">
	<tr><td>[[BHIGHPG parameter]]</td>		<tr><td>[[BHIGHPG parameter\|BHIGHPG]]</td>
	<td>Table B highest active page. Normally the high water mark of pages used (except for Hash Key and Sorted files). Viewable only. </td></tr>		<td>Table B highest active page. Normally the high water mark of pages used (except for Hash Key and Sorted files). Viewable only. </td></tr>

	<tr><td>[[BQLEN parameter]]</td>		<tr><td>[[BQLEN parameter\|BQLEN]]</td>
	<td>The number of pages in the reuse queue. Viewable only. </td></tr>		<td>The number of pages in the reuse queue. Viewable only. </td></tr>

	<tr><td>[[BRECPPG parameter]]</td>		<tr><td>[[BRECPPG parameter\|BRECPPG]]</td>
	<td>The maximum number of record slots on a Table B page. </td></tr>		<td>The maximum number of record slots on a Table B page. </td></tr>

	<tr><td>[[BRESERVE parameter]]</td>		<tr><td>[[BRESERVE parameter\|BRESERVE]]</td>
	<td>Table B Reserved space. </td></tr>		<td>Table B Reserved space. </td></tr>

	<tr><td>[[BREUSE parameter]]</td>		<tr><td>[[BREUSE parameter\|BREUSE]]</td>
	<td>The minimum percentage of free space necessary to add a page to the reuse queue, over and above BRESERVE. </td></tr>		<td>The minimum percentage of free space necessary to add a page to the reuse queue, over and above BRESERVE. </td></tr>

	<tr><td>[[BREUSED parameter]]</td>		<tr><td>[[BREUSED parameter\|BREUSED]]</td>
	<td>The numberof record slots reused. </td></tr>		<td>The numberof record slots reused. </td></tr>

	<tr><td>[[BRLIMSZ parameter]]</td>		<tr><td>[[BRLIMSZ parameter\|BRLIMSZ]]</td>
	<td>Base record size maximum. Viewable only. </td></tr>		<td>Base record size maximum. Viewable only. </td></tr>

	<tr><td>[[BSIZE parameter]]</td>		<tr><td>[[BSIZE parameter\|BSIZE]]</td>
	<td>The number of pages in Table B. </td></tr>		<td>The number of pages in Table B. </td></tr>

	<tr><td nowrap>[[RECRDOPT parameter]]</td>		<tr><td nowrap>[[RECRDOPT parameter\|RECRDOPT]]</td>
	<td>Record storage options. </td></tr>		<td>Record storage options. </td></tr>
	</table>		</table>

	[[Category:File architecture]]		[[Category:File architecture]]

JAL at 23:00, 24 January 2014

2014-01-24T23:00:08Z

Show changes

ELowell at 22:44, 18 December 2013

2013-12-18T22:44:23Z

← Older revision		Revision as of 22:44, 18 December 2013
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	<p>As of Model 204 release 7.4, Table B has a maximum number of 16.7 million record numbers (IRNs for Internal Record Numbers).		<p>As of Model 204 release 7.4, Table B has a maximum number of 16.7 million record numbers (IRNs for Internal Record Numbers).
	As of Model 204 release 7.5, Table B has a maximum number of 48 million record numbers (if FILEORG=x'200' is set). </p>		As of Model 204 release 7.5, Table B has a maximum number of 48 million record numbers (if FILEORG=x'200' is set). </p>
	If [[Table X (File ~~Architecture~~)\|Table X]] is not enabled, these 'slots' are used for both base records and extension records. If [[Table E (File architecture)\|Table E]] is not enabled, then any data with contents greater than 255 bytes must be held as a series of repeating fields.		If [[Table X (File architecture)\|Table X]] is not enabled, these 'slots' are used for both base records and extension records. If [[Table E (File architecture)\|Table E]] is not enabled, then any data with contents greater than 255 bytes must be held as a series of repeating fields.

	== Structure of a Table B page ==		== Structure of a Table B page ==

Admin at 22:32, 18 December 2013

2013-12-18T22:32:20Z

← Older revision		Revision as of 22:32, 18 December 2013
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	<p>As of Model 204 release 7.4, Table B has a maximum number of 16.7 million record numbers (IRNs for Internal Record Numbers).		<p>As of Model 204 release 7.4, Table B has a maximum number of 16.7 million record numbers (IRNs for Internal Record Numbers).
	As of Model 204 release 7.5, Table B has a maximum number of 48 million record numbers (if FILEORG=x'200' is set). </p>		As of Model 204 release 7.5, Table B has a maximum number of 48 million record numbers (if FILEORG=x'200' is set). </p>
	If [[Table X (File Architecture)\|Table X]] is not enabled, these 'slots' are used for both base records and extension records. If [[Table E (File ~~Architecture~~)\|Table E]] is not enabled, then any data with contents greater than 255 bytes must be held as a series of repeating fields.		If [[Table X (File Architecture)\|Table X]] is not enabled, these 'slots' are used for both base records and extension records. If [[Table E (File architecture)\|Table E]] is not enabled, then any data with contents greater than 255 bytes must be held as a series of repeating fields.

	== Structure of a Table B page ==		== Structure of a Table B page ==