diff options
Diffstat (limited to 'doc/src')
| -rw-r--r-- | doc/src/sgml/release.sgml | 273 |
1 files changed, 139 insertions, 134 deletions
diff --git a/doc/src/sgml/release.sgml b/doc/src/sgml/release.sgml index b7496218950..f392cab7172 100644 --- a/doc/src/sgml/release.sgml +++ b/doc/src/sgml/release.sgml @@ -1,5 +1,5 @@ <!-- -$PostgreSQL: pgsql/doc/src/sgml/release.sgml,v 1.365 2005/09/04 13:40:24 alvherre Exp $ +$PostgreSQL: pgsql/doc/src/sgml/release.sgml,v 1.366 2005/09/11 23:40:33 neilc Exp $ Typical markup: @@ -8,8 +8,7 @@ Typical markup: [A-Za-z_]/[A-Za-z_]+ <filename> PostgreSQL <productname> pg_[A-Za-z0-9_] <application> -[A-Z][A-Z] <type>, <envar. - <literal> +[A-Z][A-Z] <type>, <envar>, <literal> &<> use & --> @@ -40,10 +39,14 @@ pg_[A-Za-z0-9_] <application> <listitem> <para> - This was accomplished by eliminating global locks and using a - clock sweep algorithm to find free buffers. This increases - scalability on multi-CPU systems. - </para> + Access to the shared buffer cache was identified as a + significant scalability problem, particularly on multi-CPU + systems. In this release, the way that locking is done in the + buffer manager has been overhauled to reduce lock contention + and improve scalability. The buffer manager has also been + changed to use a <quote>clock sweep</quote> replacement + policy. + </para> </listitem> </varlistentry> @@ -56,18 +59,19 @@ pg_[A-Za-z0-9_] <application> <para> In previous releases, only a single index could be used to do lookups on a table. With this feature, if a query has - <command>WHERE tab.col1 = 4 and tab.col2 = 9</>, and there is no - multicolumn index on col1 and col2, but there is an index on - col1 and another on col2, it is possible to search both indexes - and combine the results in memory, then do heap fetches for only - the rows matching both the col1 and col2 - restrictions. This is very useful in environments that have a - lot of unstructured queries where it is impossible to create - indexes that match all possible access conditions. Bitmap scans - are useful even with a single index, as they reduce the amount - of random access needed; a bitmap index scan is efficient for - retrieving fairly large fractions of the complete table, whereas - plain index scans are not. + <command>WHERE tab.col1 = 4 and tab.col2 = 9</>, and there is + no multicolumn index on <literal>col1</> and <literal>col2</>, + but there is an index on <literal>col1</> and another on + <literal>col2</>, it is possible to search both indexes and + combine the results in memory, then do heap fetches for only + the rows matching both the <literal>col1</> and + <literal>col2</> restrictions. This is very useful in + environments that have a lot of unstructured queries where it + is impossible to create indexes that match all possible access + conditions. Bitmap scans are useful even with a single index, + as they reduce the amount of random access needed; a bitmap + index scan is efficient for retrieving fairly large fractions + of the complete table, whereas plain index scans are not. </para> </listitem> </varlistentry> @@ -165,7 +169,7 @@ pg_[A-Za-z0-9_] <application> <varlistentry> <term> Move <filename>/contrib/pg_autovacuum</> into the main server - (Alvaro Herrera) + (Alvaro) </term> <listitem> @@ -217,7 +221,7 @@ pg_[A-Za-z0-9_] <application> </sect2> <sect2> - <title>Migration to version 8.1</title> + <title>Migration to 8.1</title> <para> A dump/restore using <application>pg_dump</application> is required @@ -265,16 +269,14 @@ pg_[A-Za-z0-9_] <application> <varname>default_with_oids</> is now false by default (Neil) </para> <para> - With this option set to false, user-created tables no longer have - the usually-invisible OID column unless <command>WITH OIDS</> - is specified in <command>CREATE TABLE</>. Though OIDs have - existed in all releases of - <productname>PostgreSQL</productname>, their use is limited + With this option set to false, user-created tables no longer + have an OID column unless <command>WITH OIDS</> is specified in + <command>CREATE TABLE</>. Though OIDs have existed in all + releases of <productname>PostgreSQL</>, their use is limited because they are only four bytes long and the counter is shared across all installed databases. The preferred way of uniquely - identifying rows is via sequences and <command>SERIAL</>, which - have been supported since <productname>PostgreSQL</productname> - 6.4. + identifying rows is via sequences and the <type>SERIAL</> type, + which have been supported since <productname>PostgreSQL</> 6.4. </para> </listitem> @@ -297,21 +299,21 @@ pg_[A-Za-z0-9_] <application> syntax is formed by writing an <literal>E</> immediately preceding the single quote that starts the string, e.g. <literal>E'hi\n'</>. While this release does not change the handling of backslashes in strings, it - does add new GUC variables to help users migrate applications + does add new configuration parameters to help users migrate applications for future releases: </para> <itemizedlist> <listitem> <para> - <varname>standard_conforming_strings</> - does this release + <varname>standard_conforming_strings</> — does this release treat backslashes literally in ordinary strings? </para> </listitem> <listitem> <para> - <varname>escape_string_warning</> - warn about backslashes in + <varname>escape_string_warning</> — warn about backslashes in ordinary (non-E) strings </para> </listitem> @@ -322,18 +324,20 @@ pg_[A-Za-z0-9_] <application> The <varname>standard_conforming_strings</> value is read-only. Applications can retrieve the value to know how backslashes are processed. (Presence of the parameter can also be taken as an - indication that <literal>E''</> string syntax is supported.) In a - future release, <varname>standard_conforming_strings</> will be true, - meaning backslashes will be treated literally in non-E strings. To - prepare for this change, use <literal>E''</> strings in places that - need special backslash processing, and turn on - <varname>escape_string_warning</> to find additional strings that need - to be converted to use <literal>E''</>. Also, use two single-quotes - (<literal>''</>) to embed a literal single-quote in a string, rather - than the PostgreSQL-supported syntax of backslash single-quote - (<literal>\'</>). The former is standards-conforming and does not - require the use of the <literal>E''</> string syntax. You can also use - the <literal>$$</> string syntax, which does not treat backslashes + indication that <literal>E''</> string syntax is supported.) + In a future release, <varname>standard_conforming_strings</> + will be true, meaning backslashes will be treated literally in + non-E strings. To prepare for this change, use <literal>E''</> + strings in places that need special backslash processing, and + turn on <varname>escape_string_warning</> to find additional + strings that need to be converted to use <literal>E''</>. + Also, use two single-quotes (<literal>''</>) to embed a literal + single-quote in a string, rather than the + <productname>PostgreSQL</productname>-supported syntax of + backslash single-quote (<literal>\'</>). The former is + standards-conforming and does not require the use of the + <literal>E''</> string syntax. You can also use the + <literal>$$</> string syntax, which does not treat backslashes specially. </para> </listitem> @@ -353,8 +357,8 @@ pg_[A-Za-z0-9_] <application> <listitem> <para> - In psql, treat unquoted <literal>\{digit}+</> sequences as octal - (Bruce) + In <application>psql</application>, treat unquoted + <literal>\{digit}+</> sequences as octal (Bruce) </para> <para> In previous releases, <literal>\{digit}+</> sequences were @@ -389,8 +393,9 @@ pg_[A-Za-z0-9_] <application> <title>Additional Changes</title> <para> - Below you will find a detailed account of the additional changes - between release 8.1 and the previous major release. + Below you will find a detailed account of the additional changes + between <productname>PostgreSQL</productname> 8.1 and the + previous major release. </para> <sect3> @@ -399,7 +404,7 @@ pg_[A-Za-z0-9_] <application> <listitem> <para> - Improve rtree index capabilities and performance (Neil) + Improve GiST and rtree index performance (Neil) </para> </listitem> @@ -435,8 +440,7 @@ pg_[A-Za-z0-9_] <application> <listitem> <para> Allow non-consecutive index columns to be used in a multi-column - index - (Tom) + index (Tom) </para> <para> For example, this allows an index on columns a,b,c to be used in @@ -465,9 +469,8 @@ pg_[A-Za-z0-9_] <application> <listitem> <para> - Add GUC <varname>full_page_writes</> to control writing full - pages to WAL - (Bruce) + Add configuration parameter <varname>full_page_writes</> to + control writing full pages to WAL (Bruce) </para> <para> To prevent partial disk writes from corrupting the database, @@ -481,8 +484,9 @@ pg_[A-Za-z0-9_] <application> <listitem> <para> - Add constraint_exclusion to restrict child table lookups based - on table constraints (Simon) + Add <varname>constraint_exclusion</varname> configuration + parameter to restrict child table lookups based on table + constraints (Simon) </para> <para> This allows for a type of table partitioning. If child tables @@ -496,7 +500,8 @@ pg_[A-Za-z0-9_] <application> <listitem> <para> Use <literal>O_DIRECT</> if available when using - <literal>O_SYNC</> for wal_sync_method (Itagaki Takahiro) + <literal>O_SYNC</> for <varname>wal_sync_method</varname> + (Itagaki Takahiro) </para> <para> <literal>O_DIRECT</> causes disk writes to bypass the kernel @@ -516,12 +521,11 @@ pg_[A-Za-z0-9_] <application> </itemizedlist> </sect3> - - + <sect3> <title>Server Changes</title> <itemizedlist> - + <listitem> <para> Prevent problems due to transaction ID (XID) wraparound (Tom) @@ -551,9 +555,9 @@ pg_[A-Za-z0-9_] <application> <listitem> <para> - Add <varname>temp_buffers</> GUC variable to allow users to - determine the size of the local buffer area for temporary table - access (Tom) + Add <varname>temp_buffers</> configuration parameter to allow + users to determine the size of the local buffer area for + temporary table access (Tom) </para> </listitem> @@ -586,8 +590,9 @@ pg_[A-Za-z0-9_] <application> <listitem> <para> - Add GUC <varname>krb_server_hostname</> so the server hostname - can be specified as part of service principal (Todd Kover) + Add configuration parameter <varname>krb_server_hostname</> so + that the server hostname can be specified as part of service + principal (Todd Kover) </para> <para> If not set, any service principal matching an entry in the @@ -609,7 +614,7 @@ pg_[A-Za-z0-9_] <application> Add WAL logging for GIST indexes (Teodor, Oleg) </para> <para> - GIST indexes are now safe for crash and point-in-time recovery + GIST indexes are now safe for crash and point-in-time recovery. </para> </listitem> @@ -626,8 +631,8 @@ pg_[A-Za-z0-9_] <application> <listitem> <para> - Add GUC variables to control TCP/IP keep-alive times for idle, - interval, and count (Oliver Jowett) + Add configuration parameters to control TCP/IP keep-alive + times for idle, interval, and count (Oliver Jowett) </para> <para> @@ -650,7 +655,7 @@ pg_[A-Za-z0-9_] <application> <listitem> <para> - Allow more than two gigabyes of shared memory and per-backend + Allow more than two gigabytes of shared memory and per-backend work memory on 64-bit machines (Koichi Suzuki) </para> </listitem> @@ -665,7 +670,7 @@ pg_[A-Za-z0-9_] <application> <listitem> <para> - Add temporary views (Koju Iijima) + Add temporary views (Koju Iijima, Neil) </para> </listitem> @@ -683,12 +688,12 @@ pg_[A-Za-z0-9_] <application> <listitem> <para> Add <command>USING</> clause to allow additional tables to be - specified to <command>DELETE</> (Euler Taveira de Oliveira) + specified to <command>DELETE</> (Euler Taveira de Oliveira, Neil) </para> <para> In prior releases, there was no clear method for specifying additional tables to be used for joins in a <command>DELETE</> - statement. <command>UPDATE</> already has a <command>FROM</> + statement. <command>UPDATE</> already has a <literal>FROM</> clause for this purpose. </para> </listitem> @@ -723,14 +728,13 @@ pg_[A-Za-z0-9_] <application> UPDATE/SHARE</> (Hans-Juergen Schoenig) </para> <para> - While <command>SET</> <varname>statement_timeout</> allows a query - taking over a certain amount of time to be cancelled, the - <command>NOWAIT</> option allows a query to be canceled as soon as a - <command>SELECT ... FOR UPDATE/SHARE</> command cannot immediately - acquire a row lock. + While the <varname>statement_timeout</> configuration + parameter allows a query taking more than a certain amount of + time to be cancelled, the <command>NOWAIT</> option allows a + query to be canceled as soon as a <command>SELECT ... FOR + UPDATE/SHARE</> command cannot immediately acquire a row lock. </para> </listitem> - </itemizedlist> </sect3> @@ -781,8 +785,8 @@ pg_[A-Za-z0-9_] <application> <listitem> <para> - Add ALTER TABLE ENABLE/DISABLE TRIGGER to disable triggers - (Satoshi Nagayasu) + Add <command>ALTER TABLE ENABLE/DISABLE TRIGGER</command> to + disable triggers (Satoshi Nagayasu) </para> </listitem> @@ -812,7 +816,7 @@ pg_[A-Za-z0-9_] <application> <listitem> <para> Properly process carriage returns and line feeds in - <command>COPY CSV</> mode (Andrew Dunstan) + <command>COPY CSV</> mode (Andrew) </para> <para> In release 8.0, carriage returns and line feeds in <command>CSV @@ -876,28 +880,29 @@ pg_[A-Za-z0-9_] <application> <listitem> <para> - Make initdb create a new standard database called - <literal>postgres</>, and convert utilities to use - <literal>postgres</> rather than <literal>template1</> for + Make <application>initdb</application> create a new standard + database called <literal>postgres</>, and convert utilities to + use <literal>postgres</> rather than <literal>template1</> for standard lookups (Dave) </para> <para> - In prior releases, <literal>template1</> was used both as a default - connection for utilities like createuser, and as a template for + In prior releases, <literal>template1</> was used both as a + default connection for utilities like + <application>createuser</application>, and as a template for new databases. This caused <command>CREATE DATABASE</> to sometimes fail, because a new database cannot be created if anyone else is in the template database. With this change, the - default connection database is now <literal>postgres</>, meaning - it is much less likely someone will be using + default connection database is now <literal>postgres</>, + meaning it is much less likely someone will be using <literal>template1</> during <command>CREATE DATABASE</>. </para> </listitem> <listitem> <para> - Create new reindexdb command-line utility by moving - <filename>/contrib/reindexdb</> into the server (Euler Taveira - de Oliveira) + Create new <application>reindexdb</application> command-line + utility by moving <filename>/contrib/reindexdb</> into the + server (Euler Taveira de Oliveira) </para> </listitem> @@ -1023,8 +1028,8 @@ pg_[A-Za-z0-9_] <application> <listitem> <para> - Add <function>GREATEST()</> and <function>LEAST()</> functions - (Pavel Stehule) + Add <function>GREATEST()</> and <function>LEAST()</> variadic + functions (Pavel Stehule) </para> <para> These functions take a variable number of arguments and return @@ -1180,7 +1185,6 @@ pg_[A-Za-z0-9_] <application> </para> </listitem> - <listitem> <para> Add <function>pg_rotate_logfile()</> to force rotation of the @@ -1236,6 +1240,7 @@ pg_[A-Za-z0-9_] <application> </itemizedlist> </para> + <para> The original names still work. </para> @@ -1262,8 +1267,7 @@ pg_[A-Za-z0-9_] <application> <listitem> <para> Allow direct conversion between <literal>EUC_JP</> and - <literal>SJIS</> to improve performance (Atsushi - Ogawa) + <literal>SJIS</> to improve performance (Atsushi Ogawa) </para> </listitem> @@ -1343,8 +1347,9 @@ pg_[A-Za-z0-9_] <application> Reduce memory usage of PL/PgSQL functions (Neil) </para> <para> - Each function now has its own memory context that can be freed - when the function exits. + The parsetree of each function is now stored in a separate + memory context. This allows the memory to be easily reclaimed + when it is no longer needed. </para> </listitem> @@ -1354,8 +1359,8 @@ pg_[A-Za-z0-9_] <application> rather than at runtime (Neil) </para> <para> - Previously, syntax errors were reported only when the function - was executed. + Previously, most syntax errors were reported only when the + function was executed. </para> </listitem> @@ -1381,7 +1386,7 @@ pg_[A-Za-z0-9_] <application> <listitem> <para> Add support for an optional <command>INTO</> clause to - PL/PgSQL's <command>EXECUTE</> command (Pavel Stehule) + PL/PgSQL's <command>EXECUTE</> command (Pavel Stehule, Neil) </para> </listitem> @@ -1395,7 +1400,7 @@ pg_[A-Za-z0-9_] <application> <para> Define <literal>SQLSTATE</> and <literal>SQLERRM</> to return the <literal>SQLSTATE</> and error message of the current - exception (Pavel Stehule) + exception (Pavel Stehule, Neil) </para> <para> These variables are only accessible inside exception blocks. @@ -1405,13 +1410,13 @@ pg_[A-Za-z0-9_] <application> <listitem> <para> Allow the parameters to the <command>RAISE</> statement to be - expressions (Pavel Stehule) + expressions (Pavel Stehule, Neil) </para> </listitem> <listitem> <para> - Add a loop <command>CONTINUE</> statement (Pavel Stehule) + Add a loop <command>CONTINUE</> statement (Pavel Stehule, Neil) </para> </listitem> @@ -1442,7 +1447,7 @@ pg_[A-Za-z0-9_] <application> <listitem> <para> - Allow one-row-at-a-time retrieval of query results (Abhijit) + Allow one-row-at-a-time retrieval of query results (Abhijit Menon-Sen) </para> <para> This allows functions to use <function>spi_query()</> and @@ -1488,22 +1493,22 @@ pg_[A-Za-z0-9_] <application> <listitem> <para> - Allow <literal>strict</> mode to be enabled (Andrew) + Allow Perl's <literal>strict</> mode to be enabled (Andrew) </para> </listitem> </itemizedlist> </sect3> - - + + <sect3> <title><application>psql</> Changes</title> <itemizedlist> <listitem> <para> - Add psql <command>\set ON_ERROR_ROLLBACK</> to allow statements - in a transaction to error without affecting the rest of the + Add <command>\set ON_ERROR_ROLLBACK</> to allow statements in + a transaction to error without affecting the rest of the transaction (Greg Sabino Mullane) </para> <para> @@ -1514,8 +1519,8 @@ pg_[A-Za-z0-9_] <application> <listitem> <para> - Add support for <literal>\x</> hex strings in psql variables - (Bruce) + Add support for <literal>\x</> hex strings in + <application>psql</> variables (Bruce) </para> <para> Octal escapes were already supported. @@ -1524,14 +1529,14 @@ pg_[A-Za-z0-9_] <application> <listitem> <para> - Add psql support for <command>troff -ms</> output format (Roger + Add support for <command>troff -ms</> output format (Roger Leigh) </para> </listitem> <listitem> <para> - Allow psql's history file location to be controlled by + Allow the history file location to be controlled by <envar>HISTFILE</> (Andreas Seltenreich) </para> <para> @@ -1541,14 +1546,15 @@ pg_[A-Za-z0-9_] <application> <listitem> <para> - Prevent psql <command>\x</> (expanded mode) from affecting + Prevent <command>\x</> (expanded mode) from affecting backslash-command displays (Neil) </para> </listitem> <listitem> <para> - Add <option>-L</> option to psql to log sessions (Lorne Sunley) + Add <option>-L</> option to <application>psql</application> to + log sessions (Lorne Sunley) </para> <para> This option was added because some operating systems do not have @@ -1558,15 +1564,16 @@ pg_[A-Za-z0-9_] <application> <listitem> <para> - Make psql <command>\d</> show tablespaces of indexes (Qingqing + Make <command>\d</> show the tablespaces of indexes (Qingqing Zhou) </para> </listitem> <listitem> <para> - Allow psql help (<command>\h</>) to make a best guess on the - proper help information (Greg Sabino Mullane) + Allow <application>psql</application> help (<command>\h</>) to + make a best guess on the proper help information (Greg Sabino + Mullane) </para> <para> This allows the user to just add <command>\h</> to the front of @@ -1578,7 +1585,7 @@ pg_[A-Za-z0-9_] <application> <listitem> <para> - Add psql <command>\pset numericlocale</> to allow numbers to be + Add <command>\pset numericlocale</> to allow numbers to be output in a locale-aware format (Eugen Nedelcu) </para> <para> @@ -1609,8 +1616,7 @@ pg_[A-Za-z0-9_] <application> <listitem> <para> Allow <application>pg_dump</> to dump a consistent snapshot of - large objects - (Tom) + large objects (Tom) </para> </listitem> @@ -1644,13 +1650,13 @@ pg_[A-Za-z0-9_] <application> <sect3> - <title>libpq Changes</title> + <title><application>libpq</application> Changes</title> <itemizedlist> <listitem> <para> Add a <envar>PGPASSFILE</> environment variable to specify the - password file's filename (Andrew Dunstan) + password file's filename (Andrew) </para> </listitem> @@ -1673,8 +1679,7 @@ pg_[A-Za-z0-9_] <application> <listitem> <para> Add spinlock support for the Itanium processor using Intel - compiler (Vikram - Kalsi) + compiler (Vikram Kalsi) </para> </listitem> @@ -1699,8 +1704,8 @@ pg_[A-Za-z0-9_] <application> <listitem> <para> - Add support for wal_fsync_writethrough for Darwin (Chris - Campbell) + Add support for <literal>fsync_writethrough</literal> on + Darwin (Chris Campbell) </para> </listitem> @@ -1713,8 +1718,7 @@ pg_[A-Za-z0-9_] <application> <listitem> <para> - Allow <application>pg_config</> to be compiled using MSVC (Andrew - Dunstan) + Allow <application>pg_config</> to be compiled using MSVC (Andrew) </para> <para> This is required to build DBD::Pg using <application>MSVC</>. @@ -1727,7 +1731,7 @@ pg_[A-Za-z0-9_] <application> </para> <para> Kerberos 4 had security vulnerabilities and is no longer being - maintained by the authors. + maintained. </para> </listitem> @@ -1755,7 +1759,8 @@ pg_[A-Za-z0-9_] <application> <listitem> <para> - Allow libpq to be built thread-safe on Windows (Dave Page) + Allow <application>libpq</application> to be built thread-safe + on Windows (Dave Page) </para> </listitem> @@ -1829,7 +1834,7 @@ pg_[A-Za-z0-9_] <application> <listitem> <para> - implementation of OpenPGP symmetric-key and public-key encryption + Implementation of OpenPGP symmetric-key and public-key encryption </para> <para> Both RSA and Elgamal public-key algorithms are supported. @@ -1850,7 +1855,7 @@ pg_[A-Za-z0-9_] <application> <listitem> <para> - Take build parameters (OpenSSL, zlib) from <filename>./configure</> result + Take build parameters (OpenSSL, zlib) from <filename>configure</> result </para> <para> No need to edit the <filename>Makefile</> anymore. |