< Such indexes could be more compact if there are only a few unique values.
> Such indexes could be more compact if there are only a few distinct values.
> Such indexes can also be compressed. Keeping such indexes updated can be
> costly.
< portability issues. Anonymous mmap is required to prevent I/O
< overhead.
> portability issues. Anonymous mmap (or mmap to /dev/zero) is required
> to prevent I/O overhead.
>
> * Consider mmap()'ing files into a backend?
>
> Doing I/O to large tables would consume a lot of address space or
> require frequent mapping/unmapping. Extending the file also causes
> mapping problems that might require mapping only individual pages,
> leading to thousands of mappings. Another problem is that there is no
> way to _prevent_ I/O to disk from the dirty shared buffers so changes
> could hit disk before WAL is written.
< posix_fadvise() [fadvise]
> posix_fadvise()
>
> Posix_fadvise() can control both sequential/random file caching and
> free-behind behavior, but it is unclear how the setting affects other
> backends that also have the file open, and the feature is not supported
> on all operating systems.
>
Add explicit documentation of the recovery configuration settings. Other
minor improvements in the PITR docs. Simon Riggs, some editorialization
by Tom Lane.
< * CREATE TABLE AS can not determine column lengths from expressions [atttypmod]
> * Allow CREATE TABLE AS to determine column lengths for complex
> expressions like SELECT col1 || col2
< * Automatically create rules on views so they are updateable, per SQL99 [view]
> * Automatically create rules on views so they are updateable, per SQL99
>
> We can only auto-create rules for simple views. For more complex
> cases users will still have to write rules.
>
* Allow database recovery where tablespaces can't be created
When a pg_dump is restored, all tablespaces will attempt to be created
in their original locations. If this fails, the user must be able to
adjust the restore process.
clause implicitly whenever one is not given explicitly. Remove concept
of a schema having an associated tablespace, and simplify the rules for
selecting a default tablespace for a table or index. It's now just
(a) explicit TABLESPACE clause; (b) default_tablespace if that's not an
empty string; (c) database's default. This will allow pg_dump to use
SET commands instead of tablespace clauses to determine object locations
(but I didn't actually make it do so). All per recent discussions.
< that can spam more than one table.
> that can span more than one table.
239c239
< rather than just col1
> rather than just col1; also called skip-scanning.
641c641,642
< * Add free-behind capability for large sequential scans [fadvise]
> * Allow free-behind capability for large sequential scans, perhaps using
> posix_fadvise() [fadvise]
< * Allow the creation of bitmap indexes which can be quickly combined
< with other bitmap indexes
> * Allow non-bitmap indexes to be combined by creating bitmaps in memory
259,261c258,259
< combined. Such indexes could be more compact if there are few unique
< value. Also, perhaps they can be lossy requiring a scan of the heap page
< to find matching rows.
> combined. They can index by tid or can be lossy requiring a scan of the
> heap page to find matching rows.
263c261,262
< * Allow non-bitmap indexes to be combined
> * Allow the creation of on-disk bitmap indexes which can be quickly
> combined with other bitmap indexes
265,266c264
< Do lookups on non-bitmap indexes and create bitmaps in memory that can be
< combined with other indexes.
> Such indexes could be more compact if there are few unique value.
< * Use bitmaps to combine existing indexes [performance]
> * Allow the creation of bitmap indexes which can be quickly combined
> with other bitmap indexes
255,257c256,266
< Bitmap indexes allow single indexed columns to be combined to
< dynamically create a composite index to match a specific query. Each
< index is a bitmap, and the bitmaps are AND'ed or OR'ed to be combined.
> Bitmap indexes index single columns that can be combined with other bitmap
> indexes to dynamically create a composite index to match a specific query.
> Each index is a bitmap, and the bitmaps are bitwise AND'ed or OR'ed to be
> combined. Such indexes could be more compact if there are few unique
> value. Also, perhaps they can be lossy requiring a scan of the heap page
> to find matching rows.
>
> * Allow non-bitmap indexes to be combined
>
> Do lookups on non-bitmap indexes and create bitmaps in memory that can be
> combined with other indexes.
< This perhaps should use a round-robin allocation system where several
< tablespaces are used in a cycle. The cycle pointer should be global.
> It could start with a random tablespace from a supplied list and cycle
> through the list.
< * Add a GUC variable to control the tablespace for temporary objects
> * Add a GUC variable to control the tablespace for temporary objects and
> sort files
>
> This perhaps should use a round-robin allocation system where several
> tablespaces are used in a cycle. The cycle pointer should be global.
>
Use this new function in psql. Implement query cancellation in psql for
Windows. Code by Magnus Hagander, documentation and minor editorialization
by Tom Lane.
of HeapTupleSatisfiesItself() to trigger a hint-bit update on the tuple:
if the row was updated or deleted by a subtransaction of my own transaction
that was later rolled back. This cannot occur in pre-8.0 of course, so
the hint-bit patch applied a couple weeks ago is OK for existing releases.
But for 8.0 it seems we had better fix things so that RI_FKey_check can
pass the correct buffer number to HeapTupleSatisfiesItself. Accordingly,
add fields to the TriggerData struct to carry the buffer ID(s) for the
old and new tuple(s). There are other possible solutions but this one
seems cleanest; it will allow other AFTER-trigger functions to safely
do tqual.c calls if they want to. Put new fields at end of struct so
that there is no API breakage.
at the top level of the column's old default expression before adding
an implicit coercion to the new column type. This seems to satisfy the
principle of least surprise, as per discussion of bug #1290.
