Update reference documentation on may/can/might:

Standard English uses "may", "can", and "might" in different ways:

        may - permission, "You may borrow my rake."

        can - ability, "I can lift that log."

        might - possibility, "It might rain today."

Unfortunately, in conversational English, their use is often mixed, as
in, "You may use this variable to do X", when in fact, "can" is a better
choice.  Similarly, "It may crash" is better stated, "It might crash".

Author: bmomjian

doc/src/sgml/ref/alter_domain.sgml

@@ -1,5 +1,5 @@
 <!--
-$PostgreSQL: pgsql/doc/src/sgml/ref/alter_domain.sgml,v 1.20 2006/09/16 00:30:16 momjian Exp $
+$PostgreSQL: pgsql/doc/src/sgml/ref/alter_domain.sgml,v 1.21 2007/01/31 23:26:02 momjian Exp $
 PostgreSQL documentation
 -->
 
@@ -64,7 +64,7 @@ ALTER DOMAIN <replaceable class="PARAMETER">name</replaceable>
     <listitem>
      <para>
       These forms change whether a domain is marked to allow NULL
-      values or to reject NULL values.  You may only <literal>SET NOT NULL</>
+      values or to reject NULL values.  You can only <literal>SET NOT NULL</>
       when the columns using the domain contain no null values.
      </para>
     </listitem>

doc/src/sgml/ref/alter_index.sgml

@@ -1,5 +1,5 @@
 <!--
-$PostgreSQL: pgsql/doc/src/sgml/ref/alter_index.sgml,v 1.11 2006/09/16 00:30:16 momjian Exp $
+$PostgreSQL: pgsql/doc/src/sgml/ref/alter_index.sgml,v 1.12 2007/01/31 23:26:02 momjian Exp $
 PostgreSQL documentation
 -->
 
@@ -67,7 +67,7 @@ ALTER INDEX <replaceable class="PARAMETER">name</replaceable> RESET ( <replaceab
       <xref linkend="SQL-CREATEINDEX" endterm="sql-createindex-title">
       for details on the available parameters.  Note that the index contents
       will not be modified immediately by this command; depending on the
-      parameter you may need to rebuild the index with
+      parameter you might need to rebuild the index with
       <xref linkend="SQL-REINDEX" endterm="sql-reindex-title">
       to get the desired effects.
      </para>
@@ -80,7 +80,7 @@ ALTER INDEX <replaceable class="PARAMETER">name</replaceable> RESET ( <replaceab
      <para>
       This form resets one or more index-method-specific storage parameters to
       their defaults.  As with <literal>SET</>, a <literal>REINDEX</literal>
-      may be needed to update the index entirely.
+      might be needed to update the index entirely.
      </para>
     </listitem>
    </varlistentry>

doc/src/sgml/ref/alter_opfamily.sgml

@@ -1,5 +1,5 @@
 <!--
-$PostgreSQL: pgsql/doc/src/sgml/ref/alter_opfamily.sgml,v 1.1 2007/01/23 05:07:17 tgl Exp $
+$PostgreSQL: pgsql/doc/src/sgml/ref/alter_opfamily.sgml,v 1.2 2007/01/31 23:26:02 momjian Exp $
 PostgreSQL documentation
 -->
 
@@ -202,7 +202,7 @@ ALTER OPERATOR FAMILY <replaceable>name</replaceable> USING <replaceable class="
 
   <para>
    The <literal>OPERATOR</> and <literal>FUNCTION</>
-   clauses may appear in any order.
+   clauses can appear in any order.
   </para>
 
  </refsect1>
@@ -216,7 +216,7 @@ ALTER OPERATOR FAMILY <replaceable>name</replaceable> USING <replaceable class="
    type(s).  The name of the operator or function occupying the slot is not
    mentioned.  Also, for <literal>DROP FUNCTION</> the type(s) to specify
    are the input data type(s) the function is intended to support; for
-   GIN and GiST indexes this may have nothing to do with the actual input
+   GIN and GiST indexes this might have nothing to do with the actual input
    argument types of the function.
   </para>
 

doc/src/sgml/ref/alter_sequence.sgml

@@ -1,5 +1,5 @@
 <!--
-$PostgreSQL: pgsql/doc/src/sgml/ref/alter_sequence.sgml,v 1.15 2006/09/16 00:30:16 momjian Exp $
+$PostgreSQL: pgsql/doc/src/sgml/ref/alter_sequence.sgml,v 1.16 2007/01/31 23:26:02 momjian Exp $
 PostgreSQL documentation
 -->
 
@@ -136,7 +136,7 @@ ALTER SEQUENCE <replaceable class="parameter">name</replaceable> SET SCHEMA <rep
       <term><literal>CYCLE</literal></term>
       <listitem>
        <para>
-        The optional <literal>CYCLE</literal> key word may be used to enable
+        The optional <literal>CYCLE</literal> key word can be used to enable
         the sequence to wrap around when the
         <replaceable class="parameter">maxvalue</replaceable> or
         <replaceable class="parameter">minvalue</replaceable> has been

doc/src/sgml/ref/alter_table.sgml

@@ -1,5 +1,5 @@
 <!--
-$PostgreSQL: pgsql/doc/src/sgml/ref/alter_table.sgml,v 1.92 2006/10/23 18:10:32 petere Exp $
+$PostgreSQL: pgsql/doc/src/sgml/ref/alter_table.sgml,v 1.93 2007/01/31 23:26:02 momjian Exp $
 PostgreSQL documentation
 -->
 
@@ -110,7 +110,7 @@ where <replaceable class="PARAMETER">action</replaceable> is one of:
       These forms set or remove the default value for a column.
       The default values only apply to subsequent <command>INSERT</command>
       commands; they do not cause rows already in the table to change.
-      Defaults may also be created for views, in which case they are
+      Defaults can also be created for views, in which case they are
       inserted into <command>INSERT</> statements on the view before
       the view's <literal>ON INSERT</literal> rule is applied.
      </para>
@@ -200,7 +200,7 @@ where <replaceable class="PARAMETER">action</replaceable> is one of:
       A disabled trigger is still known to the system, but is not executed
       when its triggering event occurs.  For a deferred trigger, the enable
       status is checked when the event occurs, not when the trigger function
-      is actually executed.  One may disable or enable a single
+      is actually executed.  One can disable or enable a single
       trigger specified by name, or all triggers on the table, or only
       user triggers (this option excludes triggers that are used to implement
       foreign key constraints).  Disabling or enabling constraint triggers
@@ -261,7 +261,7 @@ where <replaceable class="PARAMETER">action</replaceable> is one of:
       <xref linkend="SQL-CREATETABLE" endterm="sql-createtable-title">
       for details on the available parameters.  Note that the table contents
       will not be modified immediately by this command; depending on the
-      parameter you may need to rewrite the table to get the desired effects.
+      parameter you might need to rewrite the table to get the desired effects.
       That can be done with <xref linkend="SQL-CLUSTER"
       endterm="sql-cluster-title"> or one of the forms of <command>ALTER
       TABLE</> that forces a table rewrite.
@@ -284,7 +284,7 @@ where <replaceable class="PARAMETER">action</replaceable> is one of:
     <listitem>
      <para>
       This form resets one or more storage parameters to their
-      defaults.  As with <literal>SET</>, a table rewrite may be
+      defaults.  As with <literal>SET</>, a table rewrite might be
       needed to update the table entirely.
      </para>
     </listitem>
@@ -309,7 +309,7 @@ where <replaceable class="PARAMETER">action</replaceable> is one of:
       <literal>CHECK</literal> constraints of the parent. Currently
       <literal>UNIQUE</literal>, <literal>PRIMARY KEY</literal>, and
       <literal>FOREIGN KEY</literal> constraints are not considered, but
-      this may change in the future.
+      this might change in the future.
      </para>
     </listitem>
    </varlistentry>
@@ -607,7 +607,7 @@ where <replaceable class="PARAMETER">action</replaceable> is one of:
    <para>
     Adding a column with a non-null default or changing the type of an
     existing column will require the entire table to be rewritten.  This
-    may take a significant amount of time for a large table; and it will
+    might take a significant amount of time for a large table; and it will
     temporarily require double the disk space.
    </para>
 
@@ -656,7 +656,7 @@ ALTER TABLE table ALTER COLUMN anycol TYPE anytype;
     expression is not applied to the column's default value (if any); the
     result might not be a constant expression as required for a default.
     This means that when there is no implicit or assignment cast from old to
-    new type, <literal>ALTER TYPE</> may fail to convert the default even
+    new type, <literal>ALTER TYPE</> might fail to convert the default even
     though a <literal>USING</literal> clause is supplied.  In such cases,
     drop the default with <literal>DROP DEFAULT</>, perform the <literal>ALTER
     TYPE</>, and then use <literal>SET DEFAULT</> to add a suitable new

doc/src/sgml/ref/analyze.sgml

@@ -1,5 +1,5 @@
 <!--
-$PostgreSQL: pgsql/doc/src/sgml/ref/analyze.sgml,v 1.20 2006/09/16 00:30:16 momjian Exp $
+$PostgreSQL: pgsql/doc/src/sgml/ref/analyze.sgml,v 1.21 2007/01/31 23:26:02 momjian Exp $
 PostgreSQL documentation
 -->
 
@@ -109,7 +109,7 @@ ANALYZE [ VERBOSE ] [ <replaceable class="PARAMETER">table</replaceable> [ (<rep
    The statistics collected by <command>ANALYZE</command> usually
    include a list of some of the most common values in each column and
    a histogram showing the approximate data distribution in each
-   column.  One or both of these may be omitted if
+   column.  One or both of these can be omitted if
    <command>ANALYZE</command> deems them uninteresting (for example,
    in a unique-key column, there are no common values) or if the
    column data type does not support the appropriate operators.  There
@@ -123,7 +123,7 @@ ANALYZE [ VERBOSE ] [ <replaceable class="PARAMETER">table</replaceable> [ (<rep
    allows even very large tables to be analyzed in a small amount of
    time.  Note, however, that the statistics are only approximate, and
    will change slightly each time <command>ANALYZE</command> is run,
-   even if the actual table contents did not change.  This may result
+   even if the actual table contents did not change.  This might result
    in small changes in the planner's estimated costs shown by
    <command>EXPLAIN</command>. In rare situations, this
    non-determinism will cause the query optimizer to choose a
@@ -146,7 +146,7 @@ ANALYZE [ VERBOSE ] [ <replaceable class="PARAMETER">table</replaceable> [ (<rep
    <command>ANALYZE</command> and the amount of space occupied in
    <literal>pg_statistic</literal>.  In particular, setting the
    statistics target to zero disables collection of statistics for
-   that column.  It may be useful to do that for columns that are
+   that column.  It might be useful to do that for columns that are
    never used as part of the <literal>WHERE</>, <literal>GROUP BY</>,
    or <literal>ORDER BY</> clauses of queries, since the planner will
    have no use for statistics on such columns.

doc/src/sgml/ref/begin.sgml

@@ -1,5 +1,5 @@
 <!--
-$PostgreSQL: pgsql/doc/src/sgml/ref/begin.sgml,v 1.34 2006/09/16 00:30:17 momjian Exp $
+$PostgreSQL: pgsql/doc/src/sgml/ref/begin.sgml,v 1.35 2007/01/31 23:26:02 momjian Exp $
 PostgreSQL documentation
 -->
 
@@ -109,7 +109,7 @@ where <replaceable class="parameter">transaction_mode</replaceable> is one of:
 
   <para>
    For reasons of backwards compatibility, the commas between successive
-   <replaceable class="parameter">transaction_modes</replaceable> may be
+   <replaceable class="parameter">transaction_modes</replaceable> can be
    omitted.
   </para>
  </refsect1>

doc/src/sgml/ref/checkpoint.sgml

@@ -1,4 +1,4 @@
-<!-- $PostgreSQL: pgsql/doc/src/sgml/ref/checkpoint.sgml,v 1.14 2006/09/16 00:30:17 momjian Exp $ -->
+<!-- $PostgreSQL: pgsql/doc/src/sgml/ref/checkpoint.sgml,v 1.15 2007/01/31 23:26:02 momjian Exp $ -->
 
 <refentry id="sql-checkpoint">
  <refmeta>
@@ -42,7 +42,7 @@ CHECKPOINT
   </para>
 
   <para>
-   Only superusers may call <command>CHECKPOINT</command>.  The command is
+   Only superusers can call <command>CHECKPOINT</command>.  The command is
    not intended for use during normal operation.
   </para>
  </refsect1>

doc/src/sgml/ref/cluster.sgml

@@ -1,5 +1,5 @@
 <!--
-$PostgreSQL: pgsql/doc/src/sgml/ref/cluster.sgml,v 1.38 2006/11/04 19:03:51 tgl Exp $
+$PostgreSQL: pgsql/doc/src/sgml/ref/cluster.sgml,v 1.39 2007/01/31 23:26:02 momjian Exp $
 PostgreSQL documentation
 -->
 
@@ -132,7 +132,7 @@ CLUSTER
     Because the planner records statistics about the ordering of
     tables, it is advisable to run <xref linkend="sql-analyze"
     endterm="sql-analyze-title"> on the newly clustered table.
-    Otherwise, the planner may make poor choices of query plans.
+    Otherwise, the planner might make poor choices of query plans.
    </para>
 
    <para>

doc/src/sgml/ref/comment.sgml

@@ -1,5 +1,5 @@
 <!--
-$PostgreSQL: pgsql/doc/src/sgml/ref/comment.sgml,v 1.34 2007/01/23 05:07:17 tgl Exp $
+$PostgreSQL: pgsql/doc/src/sgml/ref/comment.sgml,v 1.35 2007/01/31 23:26:03 momjian Exp $
 PostgreSQL documentation
 -->
 
@@ -93,7 +93,7 @@ COMMENT ON
      <para>
       The name of the object to be commented.  Names of tables,
       aggregates, domains, functions, indexes, operators, operator classes,
-      operator families, sequences, types, and views may be schema-qualified.
+      operator families, sequences, types, and views can be schema-qualified.
      </para>
     </listitem>
    </varlistentry>

doc/src/sgml/ref/copy.sgml

@@ -1,5 +1,5 @@
 <!--
-$PostgreSQL: pgsql/doc/src/sgml/ref/copy.sgml,v 1.77 2006/09/18 19:54:01 tgl Exp $
+$PostgreSQL: pgsql/doc/src/sgml/ref/copy.sgml,v 1.78 2007/01/31 23:26:03 momjian Exp $
 PostgreSQL documentation
 -->
 
@@ -358,9 +358,9 @@ COPY <replaceable class="parameter">count</replaceable>
     should not lead to problems in the event of a <command>COPY
     TO</command>, but the target table will already have received
     earlier rows in a <command>COPY FROM</command>. These rows will not
-    be visible or accessible, but they still occupy disk space. This may
+    be visible or accessible, but they still occupy disk space. This might
     amount to a considerable amount of wasted disk space if the failure
-    happened well into a large copy operation. You may wish to invoke
+    happened well into a large copy operation. You might wish to invoke
     <command>VACUUM</command> to recover the wasted space.
    </para>
  </refsect1>
@@ -395,7 +395,7 @@ COPY <replaceable class="parameter">count</replaceable>
    </para>
 
    <para>
-    Backslash characters (<literal>\</>) may be used in the
+    Backslash characters (<literal>\</>) can be used in the
     <command>COPY</command> data to quote data characters that might
     otherwise be taken as row or column delimiters. In particular, the
     following characters <emphasis>must</> be preceded by a backslash if
@@ -694,7 +694,7 @@ There is no alignment padding or any other extra data between fields.
     <para>
 Presently, all data values in a <command>COPY BINARY</command> file are
 assumed to be in binary format (format code one).  It is anticipated that a
-future extension may add a header field that allows per-column format codes
+future extension might add a header field that allows per-column format codes
 to be specified.
     </para>
 

doc/src/sgml/ref/create_aggregate.sgml

@@ -1,5 +1,5 @@
 <!--
-$PostgreSQL: pgsql/doc/src/sgml/ref/create_aggregate.sgml,v 1.36 2006/09/16 00:30:17 momjian Exp $
+$PostgreSQL: pgsql/doc/src/sgml/ref/create_aggregate.sgml,v 1.37 2007/01/31 23:26:03 momjian Exp $
 PostgreSQL documentation
 -->
 
@@ -96,7 +96,7 @@ CREATE AGGREGATE <replaceable class="PARAMETER">name</replaceable> (
   </para>
 
   <para>
-   An aggregate function may provide an initial condition,
+   An aggregate function can provide an initial condition,
    that is, an initial value for the internal state value.
    This is specified and stored in the database as a value of type
    <type>text</type>, but it must be a valid external representation

doc/src/sgml/ref/create_cast.sgml

@@ -1,4 +1,4 @@
-<!-- $PostgreSQL: pgsql/doc/src/sgml/ref/create_cast.sgml,v 1.23 2006/09/16 00:30:17 momjian Exp $ -->
+<!-- $PostgreSQL: pgsql/doc/src/sgml/ref/create_cast.sgml,v 1.24 2007/01/31 23:26:03 momjian Exp $ -->
 
 <refentry id="SQL-CREATECAST">
  <refmeta>
@@ -44,7 +44,7 @@ SELECT CAST(42 AS text);
   </para>
 
   <para>
-   Two types may be <firstterm>binary compatible</firstterm>, which
+   Two types can be <firstterm>binary compatible</firstterm>, which
    means that they can be converted into one another <quote>for
    free</quote> without invoking any function.  This requires that
    corresponding values use the same internal representation.  For
@@ -145,7 +145,7 @@ SELECT 'The time is ' || CAST(now() AS text);
 
      <listitem>
       <para>
-       The function used to perform the cast.  The function name may
+       The function used to perform the cast.  The function name can
        be schema-qualified.  If it is not, the function will be looked
        up in the schema search path.  The function's result data type must
        match the target type of the cast.   Its arguments are discussed below.
@@ -169,7 +169,7 @@ SELECT 'The time is ' || CAST(now() AS text);
 
      <listitem>
       <para>
-       Indicates that the cast may be invoked implicitly in assignment
+       Indicates that the cast can be invoked implicitly in assignment
        contexts.
       </para>
      </listitem>
@@ -180,14 +180,14 @@ SELECT 'The time is ' || CAST(now() AS text);
 
      <listitem>
       <para>
-       Indicates that the cast may be invoked implicitly in any context.
+       Indicates that the cast can be invoked implicitly in any context.
       </para>
      </listitem>
     </varlistentry>
    </variablelist>
 
   <para>
-   Cast implementation functions may have one to three arguments.
+   Cast implementation functions can have one to three arguments.
    The first argument type must be identical to the cast's source type.
    The second argument,
    if present, must be type <type>integer</>; it receives the type

doc/src/sgml/ref/create_conversion.sgml

@@ -1,4 +1,4 @@
-<!-- $PostgreSQL: pgsql/doc/src/sgml/ref/create_conversion.sgml,v 1.18 2006/09/16 00:30:17 momjian Exp $ -->
+<!-- $PostgreSQL: pgsql/doc/src/sgml/ref/create_conversion.sgml,v 1.19 2007/01/31 23:26:03 momjian Exp $ -->
 
 <refentry id="SQL-CREATECONVERSION">
  <refmeta>
@@ -27,7 +27,7 @@ CREATE [ DEFAULT ] CONVERSION <replaceable>name</replaceable>
 
   <para>
    <command>CREATE CONVERSION</command> defines a new conversion between
-   character set encodings.  Conversion names may be used in the
+   character set encodings.  Conversion names can be used in the
    <function>convert</function> function
    to specify a particular encoding conversion.  Also, conversions that
    are marked <literal>DEFAULT</> can be used for automatic encoding
@@ -65,7 +65,7 @@ CREATE [ DEFAULT ] CONVERSION <replaceable>name</replaceable>
 
      <listitem>
       <para>
-       The name of the conversion. The conversion name may be
+       The name of the conversion. The conversion name can be
        schema-qualified. If it is not, the conversion is defined in the
        current schema. The conversion name must be unique within a
        schema.
@@ -98,7 +98,7 @@ CREATE [ DEFAULT ] CONVERSION <replaceable>name</replaceable>
 
      <listitem>
       <para>
-       The function used to perform the conversion.  The function name may
+       The function used to perform the conversion.  The function name can
        be schema-qualified.  If it is not, the function will be looked
        up in the path.
       </para>
@@ -129,7 +129,7 @@ conv_proc(
   </para>
 
   <para>
-   The privileges required to create a conversion may be changed in a future
+   The privileges required to create a conversion might be changed in a future
    release.
   </para>
  </refsect1>