Not Worth Doing
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Jump to navigationJump to searchThis list contains items that were formerly on the Todo list.
Please do not add items here without discussion on the mailing list.
Administration
Allow custom variables to appear in pg_settings()
- Have custom variables be transaction-safe
- Implement the SQL-standard mechanism whereby REVOKE ROLE revokes only the privilege granted by the invoking role, and not those granted by other roles
Configuration files
- Normalizing fractions in postgresql.conf, perhaps using '%'
- Add external tool to auto-tune some postgresql.conf parameters
- Create utility to compute accurate random_page_cost value
- Allow synchronous_standby_names to be disabled after communication failure with all synchronous standby servers exceeds some timeout
- This also requires successful execution of a synchronous notification command.
- Adjust rounding behavior for numeric GUC values
Tablespaces
- Allow per-tablespace quotas
- Allow tablespaces on RAM-based partitions for temporary objects
- Close race in DROP TABLESPACE on Windows
Statistics Collector
- Track number of WAL files ready to be archived in pg_stat_archiver
Point-In-Time Recovery (PITR)
- Allow archive_mode to be changed without server restart?
Standby server mode
- Allow pg_xlogfile_name() to be used in recovery mode
- Change walsender so that it applies per-role settings
Data Types
- Fix data types where equality comparison is not intuitive, e.g. box
- Add IMMUTABLE column attribute
Domains
- Allow functions defined as casts to domains to be called during casting
- Allow values to be cast to domain types
- Make domains work better with polymorphic functions
Dates and Times
- Allow TIMESTAMP WITH TIME ZONE to store the original timezone information, either zone name or offset from UTC
- If the TIMESTAMP value is stored with a time zone name, interval computations should adjust based on the time zone rules.
- Have timestamp subtraction not call justify_hours()?
- Allow a comma to denote fractional seconds in ISO-8601-compliant times (and timestamps)
Arrays
- Add function to detect if an array is empty
- Improve handling of NULLs in arrays
MONEY Data Type
- Add locale-aware MONEY type, and support multiple currencies
- MONEY dumps in a locale-specific format making it difficult to restore to a system with a different locale
Text Search
- Allow dictionaries to change the token that is passed on to later dictionaries
- A function-based API for '@@' searches
- Improve text search error messages
- tsearch and tsdicts regression tests fail in Turkish locale on glibc
- Improve handling of dash and plus signs in email address user names, and perhaps improve URL parsing
XML
- Allow XML arrays to be cast to other data types
- Allow reliable XML operation non-UTF8 server encodings (xpath(), in particular, is known to not work)
- Move XSLT from contrib/xml2 to a more reasonable location
- Improve the XSLT parameter passing API
- xpath_table needs to be implemented/implementable to get rid of contrib/xml2 [1]
- xpath_table is pretty broken anyway [2]
- Improve handling of PIs and DTDs in xmlconcat() [5]
- Restructure XML and /contrib/xml2 functionality
Functions
- Enforce typmod for function inputs, function results and parameters for spi_prepare'd statements called from PLs
- Reduce memory usage of aggregates in set returning functions
Character Formatting
- Add missing parameter handling in to_char()
- Throw an error from to_char() instead of printing a string of "#" when a number doesn't fit in the desired output format.
- discussed in "to_char, support for EEEE format"
- Fix to_number() handling for values not matching the format string
Multi-Language Support
- Add a cares-about-collation column to pg_proc, so that unresolved-collation errors can be thrown at parse time
- Add octet_length_server() and octet_length_client()
- Make octet_length_client() the same as octet_length()?
- Fix problems with wrong runtime encoding conversion for NLS message files
Views and Rules
- Allow VIEW/RULE recompilation when the underlying tables change
- Make it possible to use RETURNING together with conditional DO INSTEAD rules, such as for partitioning setups
SQL Commands
- Add a GUC variable to warn about non-standard SQL usage in queries
- Add NOVICE output level for helpful messages
- For example, have it warn about unjoined tables. This could also control automatic sequence/index creation messages.
- Allow DISTINCT to work in multiple-argument aggregate calls
- Allow DELETE and UPDATE to be used with LIMIT and ORDER BY
Vacuum
- Auto-fill the free space map by scanning the buffer cache or by checking pages written by the background writer
Optimizer / Executor
- Increasing the default values of from_collapse_limit, join_collapse_limit, and/or geqo_threshold
- Improve use of expression indexes for ORDER BY
- Modify the planner to better estimate caching effects
- Allow shared buffer cache contents to affect index cost computations
Server-Side Languages
- Allow regex operations in PL/Perl using UTF8 characters in non-UTF8 encoded databases
Clients
psql
- Add option to print advice for people familiar with other databases
Miscellaneous Performance
- Rather than mmap()-ing in 8k pages, mmap()'ing entire 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.
Exotic Features
- Allowing control of upper/lower case folding of unquoted identifiers
- Bringing PostgreSQL torwards the standard regarding case folding
- Re: [SQL] Case Preservation disregarding case sensitivity?
- TODO Item: Consider allowing control of upper/lower case folding of unquoted, identifiers
- Identifier case folding notes
- Identifier case folding notes
- Cluster wide option to control symbol case folding
Features We Do Not Want
- Rewrite the code in a different language
- "Oracle-style" optimizer hints
- Optimizer hints, as implemented in Oracle and other RDBMSes, are used to work around problems in the optimizer and introduce upgrade and maintenance issues. We would rather have such problems reported and fixed. We have discussed a more sophisticated system of per-class cost adjustment instead, but a specification remains to be developed. See Optimizer Hints Discussion for further information.
- Embedded server
- While PostgreSQL clients runs fine in limited-resource environments, the server requires multiple processes and a stable pool of resources to run reliably and efficiently. Stripping down the PostgreSQL server to run in the same process address space as the client application would add too much complexity and failure cases. Besides, there are several very mature embedded SQL databases already available.
- Obfuscated function source code
- Obfuscating function source code has minimal protective benefits because anyone with super-user access can find a way to view the code. At the same time, it would greatly complicate backups and other administrative tasks. To prevent non-super-users from viewing function source code, remove SELECT permission on pg_proc.
- Indeterminate behavior for the GROUP BY clause
- At least one other database product allows specification of a subset of the result columns which GROUP BY would need to be able to provide predictable results; the server is free to return any value from the group. This is not viewed as a desirable feature. PostgreSQL 9.1 allows result columns that are not referenced by GROUP BY if a primary key for the same table is referenced in GROUP BY.
- On-disk bitmap indexes
- The rigidity of on-disk bitmap indexes, and the existence of GIN and in-memory bitmaps make this undesirable.
