Removes or minimizes some documentation mentions of backward
compatibility for release 7.2 and earlier. I have not altered any mentions of release 7.3 or later. The release notes were not modified, so the changes are still documented, just not in the main docs.
This commit is contained in:
parent
4799cd7f24
commit
efe3de07e9
@ -1,4 +1,4 @@
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<!-- $PostgreSQL: pgsql/doc/src/sgml/array.sgml,v 1.48 2005/11/19 01:50:08 tgl Exp $ -->
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<!-- $PostgreSQL: pgsql/doc/src/sgml/array.sgml,v 1.49 2006/04/23 03:39:47 momjian Exp $ -->
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<sect1 id="arrays">
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<sect1 id="arrays">
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<title>Arrays</title>
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<title>Arrays</title>
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@ -559,8 +559,7 @@ SELECT * FROM sal_emp WHERE 10000 = ALL (pay_by_quarter);
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embedded in element values will be backslash-escaped. For numeric
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embedded in element values will be backslash-escaped. For numeric
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data types it is safe to assume that double quotes will never appear, but
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data types it is safe to assume that double quotes will never appear, but
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for textual data types one should be prepared to cope with either presence
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for textual data types one should be prepared to cope with either presence
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or absence of quotes. (This is a change in behavior from pre-7.2
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or absence of quotes.
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<productname>PostgreSQL</productname> releases.)
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</para>
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</para>
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<para>
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<para>
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@ -1,4 +1,4 @@
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<!-- $PostgreSQL: pgsql/doc/src/sgml/backup.sgml,v 2.79 2006/03/10 19:10:46 momjian Exp $ -->
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<!-- $PostgreSQL: pgsql/doc/src/sgml/backup.sgml,v 2.80 2006/04/23 03:39:48 momjian Exp $ -->
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<chapter id="backup">
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<chapter id="backup">
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<title>Backup and Restore</title>
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<title>Backup and Restore</title>
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@ -1211,8 +1211,8 @@ restore_command = 'copy /mnt/server/archivedir/%f "%p"' # Windows
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the number after the first dot changes). This does not apply to
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the number after the first dot changes). This does not apply to
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different minor releases under the same major release (where the
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different minor releases under the same major release (where the
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number after the second dot changes); these always have compatible
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number after the second dot changes); these always have compatible
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storage formats. For example, releases 7.0.1, 7.1.2, and 7.2 are
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storage formats. For example, releases 7.2.1, 7.3.2, and 7.4 are
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not compatible, whereas 7.1.1 and 7.1.2 are. When you update
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not compatible, whereas 7.2.1 and 7.2.2 are. When you update
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between compatible versions, you can simply replace the executables
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between compatible versions, you can simply replace the executables
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and reuse the data directory on disk. Otherwise you need to back
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and reuse the data directory on disk. Otherwise you need to back
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up your data and restore it on the new server. This has to be done
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up your data and restore it on the new server. This has to be done
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@ -1,4 +1,4 @@
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<!-- $PostgreSQL: pgsql/doc/src/sgml/config.sgml,v 1.54 2006/04/18 12:41:15 momjian Exp $ -->
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<!-- $PostgreSQL: pgsql/doc/src/sgml/config.sgml,v 1.55 2006/04/23 03:39:48 momjian Exp $ -->
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<chapter Id="runtime-config">
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<chapter Id="runtime-config">
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<title>Server Configuration</title>
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<title>Server Configuration</title>
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@ -3789,14 +3789,11 @@ dynamic_library_path = 'C:\tools\postgresql;H:\my_project\lib;$libdir'
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<indexterm><primary>inheritance</></>
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<indexterm><primary>inheritance</></>
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<listitem>
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<listitem>
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<para>
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<para>
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This controls the inheritance semantics, in particular whether
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This controls the inheritance semantics. If turned <literal>off</>,
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subtables are included by various commands by default. They were
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subtables are not included by various commands by default; basically
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not included in versions prior to 7.1. If you need the old
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an implied <literal>ONLY</literal> key word. This was added for
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behavior you can set this variable to <literal>off</>, but in
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compatibility with releases prior to 7.1. See
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the long run you are encouraged to change your applications to
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<xref linkend="ddl-inherit"> for more information.
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use the <literal>ONLY</literal> key word to exclude subtables.
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See <xref linkend="ddl-inherit"> for more information about
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inheritance.
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</para>
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</para>
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</listitem>
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</listitem>
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</varlistentry>
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</varlistentry>
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@ -1,4 +1,4 @@
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<!-- $PostgreSQL: pgsql/doc/src/sgml/datatype.sgml,v 1.166 2006/03/10 19:10:47 momjian Exp $ -->
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<!-- $PostgreSQL: pgsql/doc/src/sgml/datatype.sgml,v 1.167 2006/04/23 03:39:49 momjian Exp $ -->
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<chapter id="datatype">
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<chapter id="datatype">
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<title id="datatype-title">Data Types</title>
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<title id="datatype-title">Data Types</title>
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@ -894,22 +894,14 @@ CREATE TABLE <replaceable class="parameter">tablename</replaceable> (
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string.
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string.
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</para>
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</para>
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<para>
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<para>
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If one explicitly casts a value to <type>character
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If one explicitly casts a value to <type>character
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varying(<replaceable>n</>)</type> or
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varying(<replaceable>n</>)</type> or
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<type>character(<replaceable>n</>)</type>, then an over-length
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<type>character(<replaceable>n</>)</type>, then an over-length
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value will be truncated to <replaceable>n</> characters without
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value will be truncated to <replaceable>n</> characters without
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raising an error. (This too is required by the
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raising an error. (This too is required by the
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<acronym>SQL</acronym> standard.)
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<acronym>SQL</acronym> standard.)
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</para>
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</para>
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<note>
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<para>
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Prior to <productname>PostgreSQL</> 7.2, strings that were too long were
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always truncated without raising an error, in either explicit or
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implicit casting contexts.
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</para>
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</note>
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<para>
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<para>
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The notations <type>varchar(<replaceable>n</>)</type> and
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The notations <type>varchar(<replaceable>n</>)</type> and
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@ -2899,15 +2891,6 @@ SELECT * FROM test1 WHERE a;
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</para>
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</para>
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</note>
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</note>
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<note>
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<para>
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Prior to <productname>PostgreSQL</> 7.2, <type>bit</type> data
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was always silently truncated or zero-padded on the right, with
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or without an explicit cast. This was changed to comply with the
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<acronym>SQL</acronym> standard.
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</para>
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</note>
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<para>
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<para>
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Refer to <xref
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Refer to <xref
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linkend="sql-syntax-bit-strings"> for information about the syntax
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linkend="sql-syntax-bit-strings"> for information about the syntax
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@ -1,4 +1,4 @@
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<!-- $PostgreSQL: pgsql/doc/src/sgml/datetime.sgml,v 2.48 2006/03/10 19:10:47 momjian Exp $ -->
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<!-- $PostgreSQL: pgsql/doc/src/sgml/datetime.sgml,v 2.49 2006/04/23 03:39:50 momjian Exp $ -->
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<appendix id="datetime-appendix">
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<appendix id="datetime-appendix">
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<title>Date/Time Support</title>
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<title>Date/Time Support</title>
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@ -171,10 +171,7 @@
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<tip>
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<tip>
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<para>
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<para>
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Gregorian years AD 1-99 may be entered by using 4 digits with leading
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Gregorian years AD 1-99 may be entered by using 4 digits with leading
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zeros (e.g., <literal>0099</> is AD 99). Previous versions of
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zeros (e.g., <literal>0099</> is AD 99).
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<productname>PostgreSQL</productname> accepted years with three
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digits and with single digits, but as of version 7.0 the rules have
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been tightened up to reduce the possibility of ambiguity.
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</para>
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</para>
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</tip>
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</tip>
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</para>
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</para>
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@ -1,4 +1,4 @@
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<!-- $PostgreSQL: pgsql/doc/src/sgml/ddl.sgml,v 1.55 2006/02/18 23:14:45 neilc Exp $ -->
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<!-- $PostgreSQL: pgsql/doc/src/sgml/ddl.sgml,v 1.56 2006/04/23 03:39:50 momjian Exp $ -->
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<chapter id="ddl">
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<chapter id="ddl">
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<title>Data Definition</title>
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<title>Data Definition</title>
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@ -2145,21 +2145,11 @@ VALUES ('New York', NULL, NULL, 'NY');
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<note>
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<note>
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<title>Deprecated</title>
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<title>Deprecated</title>
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<para>
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<para>
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In previous versions of <productname>PostgreSQL</productname>, the
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In releases of <productname>PostgreSQL</productname> prior to 7.1, the
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default behavior was not to include child tables in queries. This was
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default behavior was not to include child tables in queries. This was
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found to be error prone and is also in violation of the SQL
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found to be error prone and also in violation of the SQL
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standard. Under the old syntax, to include the child tables you append
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standard. You can get the pre-7.1 behavior by turning off the
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<literal>*</literal> to the table name. For example:
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<xref linkend="guc-sql-inheritance"> configuration
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<programlisting>
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SELECT * from cities*;
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</programlisting>
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You can still explicitly specify scanning child tables by
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appending <literal>*</literal>, as well as explicitly specify not
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scanning child tables by writing <literal>ONLY</literal>. But
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beginning in version 7.1, the default behavior for an undecorated
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table name is to scan its child tables too, whereas before the
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default was not to do so. To get the old default behavior,
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disable the <xref linkend="guc-sql-inheritance"> configuration
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option.
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option.
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</para>
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</para>
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</note>
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</note>
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@ -1,4 +1,4 @@
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<!-- $PostgreSQL: pgsql/doc/src/sgml/func.sgml,v 1.313 2006/03/10 20:15:25 neilc Exp $ -->
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<!-- $PostgreSQL: pgsql/doc/src/sgml/func.sgml,v 1.314 2006/04/23 03:39:50 momjian Exp $ -->
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<chapter id="functions">
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<chapter id="functions">
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<title>Functions and Operators</title>
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<title>Functions and Operators</title>
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@ -6118,14 +6118,6 @@ LOCALTIMESTAMP (<replaceable>precision</replaceable>)
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the result is given to the full available precision.
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the result is given to the full available precision.
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</para>
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</para>
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<note>
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<para>
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Prior to <productname>PostgreSQL</productname> 7.2, the precision
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parameters were unimplemented, and the result was always given
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in integer seconds.
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</para>
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</note>
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<para>
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<para>
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Some examples:
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Some examples:
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<screen>
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<screen>
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@ -1,4 +1,4 @@
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<!-- $PostgreSQL: pgsql/doc/src/sgml/libpq.sgml,v 1.206 2006/03/10 19:10:48 momjian Exp $ -->
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<!-- $PostgreSQL: pgsql/doc/src/sgml/libpq.sgml,v 1.207 2006/04/23 03:39:51 momjian Exp $ -->
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<chapter id="libpq">
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<chapter id="libpq">
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<title><application>libpq</application> - C Library</title>
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<title><application>libpq</application> - C Library</title>
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@ -686,14 +686,10 @@ PostgresPollingStatusType PQresetPoll(PGconn *conn);
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<indexterm><primary>libpq-int.h</></>
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<indexterm><primary>libpq-int.h</></>
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<application>libpq</application> application programmers should be careful to
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<application>libpq</application> application programmers should be careful to
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maintain the <structname>PGconn</structname> abstraction. Use the accessor
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maintain the <structname>PGconn</structname> abstraction. Use the accessor
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functions described below to get
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functions described below to get at the contents of <structname>PGconn</structname>.
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at the contents of <structname>PGconn</structname>. Avoid directly referencing the fields of the
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Reference to internal <structname>PGconn</structname> fields using
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<structname>PGconn</> structure because they are subject to change in the future.
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<filename>libpq-int.h</> is not recommended because they are subject to change
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(Beginning in <productname>PostgreSQL</productname> release 6.4, the
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in the future.
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definition of the <type>struct</type> behind <structname>PGconn</> is not even provided in <filename>libpq-fe.h</filename>.
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If you have old code that accesses <structname>PGconn</structname> fields directly, you can keep using it
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by including <filename>libpq-int.h</filename> too, but you are encouraged to fix the code
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soon.)
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</para>
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</para>
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</tip>
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</tip>
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@ -2972,7 +2968,7 @@ PGnotify *PQnotifies(PGconn *conn);
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typedef struct pgNotify {
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typedef struct pgNotify {
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char *relname; /* notification condition name */
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char *relname; /* notification condition name */
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int be_pid; /* process ID of server process */
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int be_pid; /* process ID of notifying server process */
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char *extra; /* notification parameter */
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char *extra; /* notification parameter */
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} PGnotify;
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} PGnotify;
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</synopsis>
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</synopsis>
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@ -2986,14 +2982,6 @@ do not represent separate allocations.
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always point to an empty string.)
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always point to an empty string.)
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</para>
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</para>
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<note>
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<para>
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In <productname>PostgreSQL</productname> 6.4 and later,
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the <structfield>be_pid</structfield> is that of the notifying server process,
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whereas in earlier versions it was always the <acronym>PID</acronym> of your own server process.
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</para>
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</note>
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<para>
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<para>
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<xref linkend="libpq-example-2"> gives a sample program that illustrates the use
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<xref linkend="libpq-example-2"> gives a sample program that illustrates the use
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of asynchronous notification.
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of asynchronous notification.
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@ -4288,16 +4276,6 @@ testlibpq.o(.text+0xa4): undefined reference to `PQerrorMessage'
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</itemizedlist>
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</itemizedlist>
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</para>
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</para>
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<para>
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<indexterm><primary>libpq-int.h</></>
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If your codes references the header file
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<filename>libpq-int.h</filename> and you refuse to fix your code to
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not use it, starting in <productname>PostgreSQL</> 7.2, this file will be found in
|
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<filename><replaceable>includedir</replaceable>/postgresql/internal/libpq-int.h</filename>,
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so you need to add the appropriate <option>-I</option> option to
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your compiler command line.
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</para>
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</sect1>
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</sect1>
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@ -1,4 +1,4 @@
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<!-- $PostgreSQL: pgsql/doc/src/sgml/lobj.sgml,v 1.39 2006/03/10 19:10:48 momjian Exp $ -->
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<!-- $PostgreSQL: pgsql/doc/src/sgml/lobj.sgml,v 1.40 2006/04/23 03:39:52 momjian Exp $ -->
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|
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<chapter id="largeObjects">
|
<chapter id="largeObjects">
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<title id="largeObjects-title">Large Objects</title>
|
<title id="largeObjects-title">Large Objects</title>
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@ -25,43 +25,26 @@
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values. This is not described here.
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values. This is not described here.
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</para>
|
</para>
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|
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<sect1 id="lo-history">
|
<sect1 id="lo-intro">
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<title>History</title>
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<title>Introduction</title>
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|
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|
<indexterm>
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|
<primary>TOAST</primary>
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|
<secondary>versus large objects</secondary>
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|
</indexterm>
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|
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<para>
|
<para>
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<productname>POSTGRES 4.2</productname>, the indirect predecessor
|
All large objects are placed in a single system table called
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of <productname>PostgreSQL</productname>, supported three standard
|
|
||||||
implementations of large objects: as files external to the
|
|
||||||
<productname>POSTGRES</productname> server, as external files
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managed by the <productname>POSTGRES</productname> server, and as
|
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data stored within the <productname>POSTGRES</productname>
|
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database. This caused considerable confusion among users. As a
|
|
||||||
result, only support for large objects as data stored within the
|
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||||||
database is retained in <productname>PostgreSQL</productname>.
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Even though this is slower to access, it provides stricter data
|
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integrity. For historical reasons, this storage scheme is
|
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referred to as <firstterm>Inversion large
|
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objects</firstterm>. (You will see the term Inversion used
|
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occasionally to mean the same thing as large object.) Since
|
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||||||
<productname>PostgreSQL 7.1</productname>, all large objects are
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placed in one system table called
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<classname>pg_largeobject</classname>.
|
<classname>pg_largeobject</classname>.
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</para>
|
<productname>PostgreSQL</productname> also supports a storage system called
|
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|
<quote><acronym>TOAST</acronym></quote> that automatically stores values
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<para>
|
larger than a single database page into a secondary storage area per table.
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<indexterm>
|
This makes the large object facility partially obsolete. One
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<primary>TOAST</primary>
|
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<secondary>versus large objects</secondary>
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||||||
</indexterm>
|
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||||||
<productname>PostgreSQL</productname> 7.1 introduced a mechanism
|
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(nicknamed <quote><acronym>TOAST</acronym></quote>) that allows
|
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||||||
data values to be much larger than single pages. This
|
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||||||
makes the large object facility partially obsolete. One
|
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||||||
remaining advantage of the large object facility is that it allows values
|
remaining advantage of the large object facility is that it allows values
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up to 2 GB in size, whereas <acronym>TOAST</acronym>ed fields can be at
|
up to 2 GB in size, whereas <acronym>TOAST</acronym>ed fields can be at
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most 1 GB. Also, large objects can be manipulated piece-by-piece much more
|
most 1 GB. Also, large objects can be randomly modified using a read/write
|
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easily than ordinary data fields, so the practical limits are considerably
|
API that is more efficient than performing such operations using
|
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different.
|
<acronym>TOAST</acronym>.
|
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</para>
|
</para>
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</sect1>
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</sect1>
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@ -70,8 +53,8 @@
|
|||||||
<title>Implementation Features</title>
|
<title>Implementation Features</title>
|
||||||
|
|
||||||
<para>
|
<para>
|
||||||
The large object implementation breaks large
|
The large object implementation breaks large
|
||||||
objects up into <quote>chunks</quote> and stores the chunks in
|
objects up into <quote>chunks</quote> and stores the chunks in
|
||||||
rows in the database. A B-tree index guarantees fast
|
rows in the database. A B-tree index guarantees fast
|
||||||
searches for the correct chunk number when doing random
|
searches for the correct chunk number when doing random
|
||||||
access reads and writes.
|
access reads and writes.
|
||||||
@ -86,10 +69,7 @@
|
|||||||
<productname>PostgreSQL</productname> client interface libraries
|
<productname>PostgreSQL</productname> client interface libraries
|
||||||
provide for accessing large objects. All large object
|
provide for accessing large objects. All large object
|
||||||
manipulation using these functions <emphasis>must</emphasis> take
|
manipulation using these functions <emphasis>must</emphasis> take
|
||||||
place within an SQL transaction block. (This requirement is
|
place within an SQL transaction block.
|
||||||
strictly enforced as of <productname>PostgreSQL 6.5</>, though it
|
|
||||||
has been an implicit requirement in previous versions, resulting
|
|
||||||
in misbehavior if ignored.)
|
|
||||||
The <productname>PostgreSQL</productname> large object interface is modeled after
|
The <productname>PostgreSQL</productname> large object interface is modeled after
|
||||||
the <acronym>Unix</acronym> file-system interface, with analogues of
|
the <acronym>Unix</acronym> file-system interface, with analogues of
|
||||||
<function>open</function>, <function>read</function>,
|
<function>open</function>, <function>read</function>,
|
||||||
|
@ -1,4 +1,4 @@
|
|||||||
<!-- $PostgreSQL: pgsql/doc/src/sgml/maintenance.sgml,v 1.54 2006/03/10 19:10:48 momjian Exp $ -->
|
<!-- $PostgreSQL: pgsql/doc/src/sgml/maintenance.sgml,v 1.55 2006/04/23 03:39:52 momjian Exp $ -->
|
||||||
|
|
||||||
<chapter id="maintenance">
|
<chapter id="maintenance">
|
||||||
<title>Routine Database Maintenance Tasks</title>
|
<title>Routine Database Maintenance Tasks</title>
|
||||||
@ -82,15 +82,9 @@
|
|||||||
</para>
|
</para>
|
||||||
|
|
||||||
<para>
|
<para>
|
||||||
Beginning in <productname>PostgreSQL</productname> 7.2, the standard form
|
The standard form of <command>VACUUM</> can run in parallel with
|
||||||
of <command>VACUUM</> can run in parallel with normal database operations
|
normal database operations (SELECTs, INSERTs, UPDATEs, DELETEs, but not
|
||||||
(selects, inserts, updates, deletes, but not changes to table definitions).
|
changes to table definitions).
|
||||||
Routine vacuuming is therefore not nearly as intrusive as it was in prior
|
|
||||||
releases, and it is not as critical to try to schedule it at low-usage
|
|
||||||
times of day.
|
|
||||||
</para>
|
|
||||||
|
|
||||||
<para>
|
|
||||||
Beginning in <productname>PostgreSQL</productname> 8.0, there are
|
Beginning in <productname>PostgreSQL</productname> 8.0, there are
|
||||||
configuration parameters that can be adjusted to further reduce the
|
configuration parameters that can be adjusted to further reduce the
|
||||||
performance impact of background vacuuming. See
|
performance impact of background vacuuming. See
|
||||||
@ -245,12 +239,9 @@
|
|||||||
It is possible to run <command>ANALYZE</> on specific tables and even
|
It is possible to run <command>ANALYZE</> on specific tables and even
|
||||||
just specific columns of a table, so the flexibility exists to update some
|
just specific columns of a table, so the flexibility exists to update some
|
||||||
statistics more frequently than others if your application requires it.
|
statistics more frequently than others if your application requires it.
|
||||||
In practice, however, the usefulness of this feature is doubtful.
|
In practice, however, it is usually best to just analyze the entire database
|
||||||
Beginning in <productname>PostgreSQL</productname> 7.2,
|
because it is a fast operation. It uses a statistical random sampling of
|
||||||
<command>ANALYZE</> is a fairly fast operation even on large tables,
|
the rows of a table rather than reading every single row.
|
||||||
because it uses a statistical random sampling of the rows of a table
|
|
||||||
rather than reading every single row. So it's probably much simpler
|
|
||||||
to just run it over the whole database every so often.
|
|
||||||
</para>
|
</para>
|
||||||
|
|
||||||
<tip>
|
<tip>
|
||||||
@ -295,18 +286,8 @@
|
|||||||
transactions that were in the past appear to be in the future — which
|
transactions that were in the past appear to be in the future — which
|
||||||
means their outputs become invisible. In short, catastrophic data loss.
|
means their outputs become invisible. In short, catastrophic data loss.
|
||||||
(Actually the data is still there, but that's cold comfort if you can't
|
(Actually the data is still there, but that's cold comfort if you can't
|
||||||
get at it.)
|
get at it.) To avoid this, it is <emphasis>necessary to vacuum every table
|
||||||
</para>
|
in every database at least once every billion transactions</emphasis>.
|
||||||
|
|
||||||
<para>
|
|
||||||
Prior to <productname>PostgreSQL</productname> 7.2, the only defense
|
|
||||||
against XID wraparound was to re-<command>initdb</> at least every 4
|
|
||||||
billion transactions. This of course was not very satisfactory for
|
|
||||||
high-traffic sites, so a better solution has been devised. The new
|
|
||||||
approach allows a server to remain up indefinitely, without
|
|
||||||
<command>initdb</> or any sort of restart. The price is this
|
|
||||||
maintenance requirement: <emphasis>every table in the database must
|
|
||||||
be vacuumed at least once every billion transactions</emphasis>.
|
|
||||||
</para>
|
</para>
|
||||||
|
|
||||||
<para>
|
<para>
|
||||||
|
@ -1,4 +1,4 @@
|
|||||||
<!-- $PostgreSQL: pgsql/doc/src/sgml/mvcc.sgml,v 2.55 2006/03/10 19:10:48 momjian Exp $ -->
|
<!-- $PostgreSQL: pgsql/doc/src/sgml/mvcc.sgml,v 2.56 2006/04/23 03:39:52 momjian Exp $ -->
|
||||||
|
|
||||||
<chapter id="mvcc">
|
<chapter id="mvcc">
|
||||||
<title>Concurrency Control</title>
|
<title>Concurrency Control</title>
|
||||||
@ -899,10 +899,6 @@ UPDATE accounts SET balance = balance - 100.00 WHERE acctnum = 22222;
|
|||||||
TABLE</command> locks the whole table.) This should be taken into
|
TABLE</command> locks the whole table.) This should be taken into
|
||||||
account when porting applications to
|
account when porting applications to
|
||||||
<productname>PostgreSQL</productname> from other environments.
|
<productname>PostgreSQL</productname> from other environments.
|
||||||
(Before version 6.5 <productname>PostgreSQL</productname> used
|
|
||||||
read locks, and so this above consideration is also relevant when
|
|
||||||
upgrading from <productname>PostgreSQL</productname> versions
|
|
||||||
prior to 6.5.)
|
|
||||||
</para>
|
</para>
|
||||||
|
|
||||||
<para>
|
<para>
|
||||||
|
@ -1,4 +1,4 @@
|
|||||||
<!-- $PostgreSQL: pgsql/doc/src/sgml/rules.sgml,v 1.44 2005/10/22 14:44:35 alvherre Exp $ -->
|
<!-- $PostgreSQL: pgsql/doc/src/sgml/rules.sgml,v 1.45 2006/04/23 03:39:52 momjian Exp $ -->
|
||||||
|
|
||||||
<chapter id="rules">
|
<chapter id="rules">
|
||||||
<title>The Rule System</title>
|
<title>The Rule System</title>
|
||||||
@ -2043,10 +2043,7 @@ Nestloop
|
|||||||
<para>
|
<para>
|
||||||
Another situation is cases on <command>UPDATE</command> where it depends on the
|
Another situation is cases on <command>UPDATE</command> where it depends on the
|
||||||
change of an attribute if an action should be performed or
|
change of an attribute if an action should be performed or
|
||||||
not. In <productname>PostgreSQL</productname> version 6.4, the
|
not. The only way to
|
||||||
attribute specification for rule events is disabled (it will have
|
|
||||||
its comeback latest in 6.5, maybe earlier
|
|
||||||
- stay tuned). So for now the only way to
|
|
||||||
create a rule as in the shoelace_log example is to do it with
|
create a rule as in the shoelace_log example is to do it with
|
||||||
a rule qualification. That results in an extra query that is
|
a rule qualification. That results in an extra query that is
|
||||||
performed always, even if the attribute of interest cannot
|
performed always, even if the attribute of interest cannot
|
||||||
|
@ -1,4 +1,4 @@
|
|||||||
<!-- $PostgreSQL: pgsql/doc/src/sgml/storage.sgml,v 1.9 2006/03/10 19:10:49 momjian Exp $ -->
|
<!-- $PostgreSQL: pgsql/doc/src/sgml/storage.sgml,v 1.10 2006/04/23 03:39:52 momjian Exp $ -->
|
||||||
|
|
||||||
<chapter id="storage">
|
<chapter id="storage">
|
||||||
|
|
||||||
@ -187,15 +187,13 @@ Oversized-Attribute Storage Technique).
|
|||||||
</para>
|
</para>
|
||||||
|
|
||||||
<para>
|
<para>
|
||||||
Since <productname>PostgreSQL</productname> uses a fixed page size (commonly
|
<productname>PostgreSQL</productname> uses a fixed page size (commonly
|
||||||
8Kb), and does not allow tuples to span multiple pages, it's not possible to
|
8Kb), and does not allow tuples to span multiple pages. Therefore, it is
|
||||||
store very large field values directly. Before <productname>PostgreSQL</> 7.1
|
not possible to store very large field values directly. To overcome
|
||||||
there was a hard limit of just under one page on the total amount of data that
|
this limitation, large field values are compressed and/or broken up into
|
||||||
could be put into a table row. In release 7.1 and later, this limit is
|
multiple physical rows. This happens transparently to the user, with only
|
||||||
overcome by allowing large field values to be compressed and/or broken up into
|
small impact on most of the backend code. The technique is affectionately
|
||||||
multiple physical rows. This happens transparently to the user, with only
|
known as <acronym>TOAST</> (or <quote>the best thing since sliced bread</>).
|
||||||
small impact on most of the backend code. The technique is affectionately
|
|
||||||
known as <acronym>TOAST</> (or <quote>the best thing since sliced bread</>).
|
|
||||||
</para>
|
</para>
|
||||||
|
|
||||||
<para>
|
<para>
|
||||||
|
@ -1,4 +1,4 @@
|
|||||||
<!-- $PostgreSQL: pgsql/doc/src/sgml/xfunc.sgml,v 1.111 2006/03/10 19:10:49 momjian Exp $ -->
|
<!-- $PostgreSQL: pgsql/doc/src/sgml/xfunc.sgml,v 1.112 2006/04/23 03:39:52 momjian Exp $ -->
|
||||||
|
|
||||||
<sect1 id="xfunc">
|
<sect1 id="xfunc">
|
||||||
<title>User-Defined Functions</title>
|
<title>User-Defined Functions</title>
|
||||||
@ -1192,15 +1192,6 @@ CREATE FUNCTION square_root(double precision) RETURNS double precision
|
|||||||
command <literal>pg_config --pkglibdir</literal>.
|
command <literal>pg_config --pkglibdir</literal>.
|
||||||
</para>
|
</para>
|
||||||
|
|
||||||
<para>
|
|
||||||
Before <productname>PostgreSQL</productname> release 7.2, only
|
|
||||||
exact absolute paths to object files could be specified in
|
|
||||||
<command>CREATE FUNCTION</>. This approach is now deprecated
|
|
||||||
since it makes the function definition unnecessarily unportable.
|
|
||||||
It's best to specify just the shared library name with no path nor
|
|
||||||
extension, and let the search mechanism provide that information
|
|
||||||
instead.
|
|
||||||
</para>
|
|
||||||
</sect2>
|
</sect2>
|
||||||
|
|
||||||
<sect2 id="xfunc-c-basetype">
|
<sect2 id="xfunc-c-basetype">
|
||||||
@ -1915,15 +1906,7 @@ concat_text(PG_FUNCTION_ARGS)
|
|||||||
--includedir-server</literal><indexterm><primary>pg_config</><secondary>with user-defined C functions</></>
|
--includedir-server</literal><indexterm><primary>pg_config</><secondary>with user-defined C functions</></>
|
||||||
to find out where the <productname>PostgreSQL</> server header
|
to find out where the <productname>PostgreSQL</> server header
|
||||||
files are installed on your system (or the system that your
|
files are installed on your system (or the system that your
|
||||||
users will be running on). This option is new with
|
users will be running on).
|
||||||
<productname>PostgreSQL</> 7.2. For
|
|
||||||
<productname>PostgreSQL</> 7.1 you should use the option
|
|
||||||
<option>--includedir</option>. (<command>pg_config</command>
|
|
||||||
will exit with a non-zero status if it encounters an unknown
|
|
||||||
option.) For releases prior to 7.1 you will have to guess,
|
|
||||||
but since that was before the current calling conventions were
|
|
||||||
introduced, it is unlikely that you want to support those
|
|
||||||
releases.
|
|
||||||
</para>
|
</para>
|
||||||
</listitem>
|
</listitem>
|
||||||
|
|
||||||
|
Loading…
x
Reference in New Issue
Block a user