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Remove zero_damaged_pages from postgresql.conf.sample; the only way to
find out about it is to read the documentation that tells you how dangerous it is. Add default_transaction_read_only to documentation; seems to have been overlooked in patch that added read-only transactions. Clean up check_guc comparison script, which has been suffering bit rot.
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-24
lines changed

3 files changed

+50
-24
lines changed

‎doc/src/sgml/runtime.sgml

Lines changed: 24 additions & 3 deletions
Original file line numberDiff line numberDiff line change
@@ -1,5 +1,5 @@
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<!--
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$Header: /cvsroot/pgsql/doc/src/sgml/runtime.sgml,v 1.175 2003/03/28 20:17:13 tgl Exp $
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$Header: /cvsroot/pgsql/doc/src/sgml/runtime.sgml,v 1.176 2003/04/03 23:32:47 tgl Exp $
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-->
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<Chapter Id="runtime">
@@ -1476,6 +1476,25 @@ SET ENABLE_SEQSCAN TO OFF;
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</listitem>
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</varlistentry>
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<varlistentry>
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<indexterm>
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<primary>read-only transaction</primary>
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</indexterm>
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<term><varname>DEFAULT_TRANSACTION_READ_ONLY</varname> (<type>boolean</type>)</term>
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<listitem>
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<para>
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A read-only SQL transaction cannot alter non-temporary tables.
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This parameter controls the default read-only status of each new
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transaction. The default is false (read/write).
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</para>
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<para>
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Consult <xref linkend="sql-set-transaction"> for more information.
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</para>
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</listitem>
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</varlistentry>
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<varlistentry>
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<term><varname>DYNAMIC_LIBRARY_PATH</varname> (<type>string</type>)</term>
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<indexterm><primary>dynamic_library_path</></>
@@ -2182,11 +2201,13 @@ dynamic_library_path = '/usr/local/lib/postgresql:/home/my_project/lib:$libdir'
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<productname>PostgreSQL</> to report an error, aborting the current
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transaction. Setting <varname>zero_damaged_pages</> to true causes
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the system to instead report a warning, zero out the damaged page,
2185-
and continue processing. This behavior <emphasis>will lose data</>,
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and continue processing. This behavior <emphasis>will destroy data</>,
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namely all the rows on the damaged page. But it allows you to get
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past the error and retrieve rows from any undamaged pages that may
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be present in the table. So it is useful for recovering data if
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corruption has occurred due to hardware or software error. The
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corruption has occurred due to hardware or software error. You should
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generally not set this true until you have given up hope of recovering
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data from the damaged page(s) of a table. The
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default setting is off, and it can only be changed by a superuser.
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</para>
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</listitem>

‎src/backend/utils/misc/check_guc

Lines changed: 25 additions & 20 deletions
Original file line numberDiff line numberDiff line change
@@ -1,21 +1,24 @@
11
#!/bin/sh
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33
## currently, this script makes a lot of assumptions:
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## 1) the valid config settings may be preceded by a '#', but NOT '# '
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## (we use this to skip comments)
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## 2) the valid config settings will be followed immediately by ' ='
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## (at least one space preceding the '=' for guc.c)
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## 3) the options have PGC_ on the same line as the option
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## 4) the options have '{ ' on the same line as the option
4+
## in postgresql.conf.sample:
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## 1) the valid config settings may be preceded by a '#', but NOT '# '
6+
## (we use this to skip comments)
7+
## 2) the valid config settings will be followed immediately by ' ='
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## (at least one space preceding the '=')
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## in guc.c:
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## 3) the options have PGC_ on the same line as the option
11+
## 4) the options have '{' on the same line as the option
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## Problems
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## 1) Don't know what to do with TRANSACTION ISOLATION LEVEL
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## if an option is valid but shows up in only one file (guc.c or
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## postgresql.conf.sample, it should be listed here so that it
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## if an option is valid but shows up in only one file (guc.c but not
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## postgresql.conf.sample), it should be listed here so that it
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## can be ignored
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INTENTIONALLY_NOT_INCLUDED="pre_auth_delay lc_messages lc_monetary \
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lc_time lc_numeric server_encoding session_authorization"
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lc_numeric lc_time seed server_encoding session_authorization \
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transaction_isolation transaction_read_only zero_damaged_pages"
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### What options are listed in postgresql.conf.sample, but don't appear
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### in guc.c?
@@ -26,19 +29,19 @@ grep -v '^# ' | # strip comments
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sed -e 's/^#//' |
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awk '{print $1}'`
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SETTINGS=`echo "$SETTINGS" |
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tr 'A-Z' 'a-z' # lowercase`
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SETTINGS=`echo "$SETTINGS" | tr 'A-Z' 'a-z'`
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for i in $SETTINGS ; do
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hidden=0
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## it sure would be nice to replace this with an sql "not in" statement
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for hidethis in $INTENTIONALLY_NOT_INCLUDED ; do
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if [ "$hidethis" = "$i" ] ; then
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hidden=1
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fi
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done
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## it doesn't seem to make sense to have things in .sample and not in guc.c
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# for hidethis in $INTENTIONALLY_NOT_INCLUDED ; do
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# if [ "$hidethis" = "$i" ] ; then
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# hidden=1
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# fi
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# done
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if [ "$hidden" -eq 0 ] ; then
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grep -i $i guc.c > /dev/null
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grep -i '"'$i'"' guc.c > /dev/null
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if [ $? -ne 0 ] ; then
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echo "$i seems to be missing from guc.c";
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fi;
@@ -50,19 +53,21 @@ done
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# grab everything that looks like a setting and convert it to lower case
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SETTINGS=`grep '{ .*PGC_' guc.c | awk '{print $2}' | \
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sed -e 's/"//g' -e 's/,//'`
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SETTINGS=`grep '{.* PGC_' guc.c | awk '{print $1}' | \
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sed -e 's/{//g' -e 's/"//g' -e 's/,//'`
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5559
SETTINGS=`echo "$SETTINGS" | tr 'A-Z' 'a-z'`
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for i in $SETTINGS ; do
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hidden=0
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## it sure would be nice to replace this with an sql "not in" statement
5964
for hidethis in $INTENTIONALLY_NOT_INCLUDED ; do
6065
if [ "$hidethis" = "$i" ] ; then
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hidden=1
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fi
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done
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if [ "$hidden" -eq 0 ] ; then
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grep -i $i postgresql.conf.sample > /dev/null
70+
grep -i '#'$i' ' postgresql.conf.sample > /dev/null
6671
if [ $? -ne 0 ] ; then
6772
echo "$i seems to be missing from postgresql.conf.sample";
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fi

‎src/backend/utils/misc/postgresql.conf.sample

Lines changed: 1 addition & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -205,6 +205,7 @@
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#authentication_timeout = 60 # 1-600, in seconds
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#deadlock_timeout = 1000 # in milliseconds
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#default_transaction_isolation = 'read committed'
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#default_transaction_read_only = false
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#extra_float_digits = 0 # min -15, max 2
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#max_expr_depth = 10000 # min 10
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#max_files_per_process = 1000 # min 25
@@ -213,6 +214,5 @@
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#sql_inheritance = true
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#transform_null_equals = false
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#statement_timeout = 0 # 0 is disabled, in milliseconds
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#zero_damaged_pages = false # set this true only for disaster recovery
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#db_user_namespace = false
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#preload_libraries = ''

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