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Add third idea about pulling data from indexes.
> A third idea would be for a heap scan to check if all rows are visible > and if so set a per-table flag which can be checked by index scans. > Any change to the table would have to clear the flag. To detect > changes during the heap scan a counter could be set at the start and > checked at the end --- if it is the same, the table has not been > modified --- any table change would increment the counter.
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@ -8,7 +8,7 @@
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<body bgcolor="#FFFFFF" text="#000000" link="#FF0000" vlink="#A00000" alink="#0000FF">
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<body bgcolor="#FFFFFF" text="#000000" link="#FF0000" vlink="#A00000" alink="#0000FF">
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<h1><a name="section_1">PostgreSQL TODO List</a></h1>
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<h1><a name="section_1">PostgreSQL TODO List</a></h1>
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<p>Current maintainer: Bruce Momjian (<a href="mailto:bruce@momjian.us">bruce@momjian.us</a>)<br/>
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<p>Current maintainer: Bruce Momjian (<a href="mailto:bruce@momjian.us">bruce@momjian.us</a>)<br/>
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Last updated: Wed Aug 15 11:36:16 EDT 2007
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Last updated: Wed Aug 15 11:48:07 EDT 2007
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</p>
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</p>
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<p>The most recent version of this document can be viewed at<br/>
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<p>The most recent version of this document can be viewed at<br/>
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<a href="http://www.postgresql.org/docs/faqs.TODO.html">http://www.postgresql.org/docs/faqs.TODO.html</a>.
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<a href="http://www.postgresql.org/docs/faqs.TODO.html">http://www.postgresql.org/docs/faqs.TODO.html</a>.
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@ -1010,6 +1010,13 @@ first. There is also a developer's wiki at<br/>
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add someday to determine which heap pages need vacuuming. Frequently
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add someday to determine which heap pages need vacuuming. Frequently
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accessed bitmaps would have to be stored in shared memory. One 8k
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accessed bitmaps would have to be stored in shared memory. One 8k
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page of bitmaps could track 512MB of heap pages.
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page of bitmaps could track 512MB of heap pages.
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</p>
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<p> A third idea would be for a heap scan to check if all rows are visible
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and if so set a per-table flag which can be checked by index scans.
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Any change to the table would have to clear the flag. To detect
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changes during the heap scan a counter could be set at the start and
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checked at the end --- if it is the same, the table has not been
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modified --- any table change would increment the counter.
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</p>
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</p>
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</li><li>Consider automatic caching of statements at various levels:
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</li><li>Consider automatic caching of statements at various levels:
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<ul>
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<ul>
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