mirror of
				https://github.com/postgres/postgres.git
				synced 2025-11-04 00:02:52 -05:00 
			
		
		
		
	Update entry:
< * Allow heap reuse of UPDATEd rows if old and new versions are on the < same heap page? > * Allow heap reuse of UPDATEd rows if no indexed columns are changed, > and old and new versions are on the same heap page? < This is possible for same-page updates because a single index row < can point to both old and new values. > While vacuum handles DELETEs fine, updating of non-indexed columns, like > counters, are difficult for VACUUM to handle efficiently. This method > is possible for same-page updates because a single index row can be > used to point to both old and new values.
This commit is contained in:
		
							parent
							
								
									fc6a2293b5
								
							
						
					
					
						commit
						ac7a126d0c
					
				
							
								
								
									
										12
									
								
								doc/TODO
									
									
									
									
									
								
							
							
						
						
									
										12
									
								
								doc/TODO
									
									
									
									
									
								
							@ -2,7 +2,7 @@
 | 
			
		||||
PostgreSQL TODO List
 | 
			
		||||
====================
 | 
			
		||||
Current maintainer:	Bruce Momjian (bruce@momjian.us)
 | 
			
		||||
Last updated:		Sat Jun 24 19:44:48 EDT 2006
 | 
			
		||||
Last updated:		Sat Jun 24 19:47:53 EDT 2006
 | 
			
		||||
 | 
			
		||||
The most recent version of this document can be viewed at
 | 
			
		||||
http://www.postgresql.org/docs/faqs.TODO.html.
 | 
			
		||||
@ -1131,11 +1131,13 @@ Vacuum
 | 
			
		||||
 | 
			
		||||
  http://archives.postgresql.org/pgsql-patches/2006-03/msg00142.php
 | 
			
		||||
 | 
			
		||||
* Allow heap reuse of UPDATEd rows if old and new versions are on the
 | 
			
		||||
  same heap page?
 | 
			
		||||
* Allow heap reuse of UPDATEd rows if no indexed columns are changed,
 | 
			
		||||
  and old and new versions are on the same heap page?
 | 
			
		||||
 | 
			
		||||
  This is possible for same-page updates because a single index row
 | 
			
		||||
  can point to both old and new values.
 | 
			
		||||
  While vacuum handles DELETEs fine, updating of non-indexed columns, like
 | 
			
		||||
  counters, are difficult for VACUUM to handle efficiently.  This method
 | 
			
		||||
  is possible for same-page updates because a single index row can be
 | 
			
		||||
  used to point to both old and new values.
 | 
			
		||||
  http://archives.postgresql.org/pgsql-hackers/2006-06/msg01305.php
 | 
			
		||||
 | 
			
		||||
* Auto-vacuum
 | 
			
		||||
 | 
			
		||||
@ -8,7 +8,7 @@
 | 
			
		||||
<body bgcolor="#FFFFFF" text="#000000" link="#FF0000" vlink="#A00000" alink="#0000FF">
 | 
			
		||||
<h1><a name="section_1">PostgreSQL TODO List</a></h1>
 | 
			
		||||
<p>Current maintainer:     Bruce Momjian (<a href="mailto:bruce@momjian.us">bruce@momjian.us</a>)<br/>
 | 
			
		||||
Last updated:           Sat Jun 24 19:44:48 EDT 2006
 | 
			
		||||
Last updated:           Sat Jun 24 19:47:53 EDT 2006
 | 
			
		||||
</p>
 | 
			
		||||
<p>The most recent version of this document can be viewed at<br/>
 | 
			
		||||
<a href="http://www.postgresql.org/docs/faqs.TODO.html">http://www.postgresql.org/docs/faqs.TODO.html</a>.
 | 
			
		||||
@ -1020,10 +1020,12 @@ first.
 | 
			
		||||
  </li><li>Consider shrinking expired tuples to just their headers
 | 
			
		||||
<p>  <a href="http://archives.postgresql.org/pgsql-patches/2006-03/msg00142.php">http://archives.postgresql.org/pgsql-patches/2006-03/msg00142.php</a>
 | 
			
		||||
</p>
 | 
			
		||||
  </li><li>Allow heap reuse of UPDATEd rows if old and new versions are on the
 | 
			
		||||
  same heap page?
 | 
			
		||||
<p>  This is possible for same-page updates because a single index row
 | 
			
		||||
  can point to both old and new values.
 | 
			
		||||
  </li><li>Allow heap reuse of UPDATEd rows if no indexed columns are changed,
 | 
			
		||||
  and old and new versions are on the same heap page?
 | 
			
		||||
<p>  While vacuum handles DELETEs fine, updating of non-indexed columns, like
 | 
			
		||||
  counters, are difficult for VACUUM to handle efficiently.  This method
 | 
			
		||||
  is possible for same-page updates because a single index row can be
 | 
			
		||||
  used to point to both old and new values.
 | 
			
		||||
  <a href="http://archives.postgresql.org/pgsql-hackers/2006-06/msg01305.php">http://archives.postgresql.org/pgsql-hackers/2006-06/msg01305.php</a>
 | 
			
		||||
</p>
 | 
			
		||||
  </li><li>Auto-vacuum
 | 
			
		||||
 | 
			
		||||
		Loading…
	
	
			
			x
			
			
		
	
		Reference in New Issue
	
	Block a user