Update ref/prefpare.sgml

ref/prefpare.sgml 调整内容(2019.12.15)：

row6：
	根据WinMerge比较结果，将
		"<refentry id="SQL-PREPARE">"
		调整为小写
		"<refentry id="sql-prepare">"

row93
	根据WinMerge比较结果，将
	"in which the parameter is used (if possible)."
	调整为新内容
	"in which the parameter is first referenced (if possible)."
row101
	根据row93英文内容变化，将
	"其类型会从该参数被使用的环境中推知（如果可能）"
	调整为新翻译内容
	"其类型会从该参数第一次被引用的环境中推知（如果可能）"

row174
	根据WinMerge比较结果，将
	"from the context in which the parameter is used."
	调整为新内容
	"from the context in which the parameter is first referenced."
row180
	根据row174英文内容变化，将
	"将从该参数被使用的环境中推得"
	调整为新翻译内容
	"将从该参数第一次被引用的环境中推得"

row206
	根据WinMerge比较结果，将
	"<refsect1 id="SQL-PREPARE-notes">"
	调整为小写
	"<refsect1 id="sql-prepare-notes">"

其他更新
	将英文原文中的</>补充相应tag

	注1. 潜在疑问，
   	"<literal>$<replaceable>n</></literal>"
	是否应替换为
	"   <literal>$<replaceable>n</replaceable></literal>"

Author: chegong18

postgresql/doc/src/sgml/ref/prepare.sgml

@@ -3,7 +3,7 @@ doc/src/sgml/ref/prepare.sgml
 PostgreSQL documentation
 -->
 
-<refentry id="SQL-PREPARE">
+<refentry id="sql-prepare">
 <!--==========================orignal english content==========================
  <indexterm zone="sql-prepare">
   <primary>PREPARE</primary>
@@ -86,19 +86,19 @@ ____________________________________________________________________________-->
    Prepared statements can take parameters: values that are
    substituted into the statement when it is executed. When creating
    the prepared statement, refer to parameters by position, using
-   <literal>$1</>, <literal>$2</>, etc. A corresponding list of
+   <literal>$1</literal>, <literal>$2</literal>, etc. A corresponding list of
    parameter data types can optionally be specified. When a
    parameter's data type is not specified or is declared as
    <literal>unknown</literal>, the type is inferred from the context
-   in which the parameter is used (if possible). When executing the
+   in which the parameter is first referenced (if possible). When executing the
    statement, specify the actual values for these parameters in the
    <command>EXECUTE</command> statement.  Refer to <xref
    linkend="sql-execute"> for more
    information about that.
   </para>
 ____________________________________________________________________________-->
   <para>
-   预备语句可以接受参数：在执行时会被替换到语句中的值。在创建预备语句时，可以用位置引用参数，如<literal>$1</literal>、<literal>$2</literal>等。也可以选择性地指定参数数据类型的一个列表。当一个参数的数据类型没有被指定或者被声明为<literal>unknown</literal>时，其类型会从该参数被使用的环境中推知（如果可能）。在执行该语句时，在<command>EXECUTE</command>语句中为这些参数指定实际值。更多有关于此的信息可参考<xref linkend="sql-execute"/>。
+   预备语句可以接受参数：在执行时会被替换到语句中的值。在创建预备语句时，可以用位置引用参数，如<literal>$1</literal>、<literal>$2</literal>等。也可以选择性地指定参数数据类型的一个列表。当一个参数的数据类型没有被指定或者被声明为<literal>unknown</literal>时，其类型会从该参数第一次被引用的环境中推知（如果可能）。在执行该语句时，在<command>EXECUTE</command>语句中为这些参数指定实际值。更多有关于此的信息可参考<xref linkend="sql-execute"/>。
   </para>
 
 <!--==========================orignal english content==========================
@@ -171,13 +171,13 @@ ____________________________________________________________________________-->
       The data type of a parameter to the prepared statement.  If the
       data type of a particular parameter is unspecified or is
       specified as <literal>unknown</literal>, it will be inferred
-      from the context in which the parameter is used. To refer to the
+      from the context in which the parameter is first referenced. To refer to the
       parameters in the prepared statement itself, use
       <literal>$1</literal>, <literal>$2</literal>, etc.
      </para>
 ____________________________________________________________________________-->
      <para>
-      预备语句一个参数的数据类型。如果一个特定参数的数据类型没有被指定或者被指定为<literal>unknown</literal>，将从该参数被使用的环境中推得。要在预备语句本身中引用参数，可以使用
+      预备语句一个参数的数据类型。如果一个特定参数的数据类型没有被指定或者被指定为<literal>unknown</literal>，将从该参数第一次被引用的环境中推得。要在预备语句本身中引用参数，可以使用
       <literal>$1</literal>、<literal>$2</literal>等。
      </para>
     </listitem>
@@ -191,8 +191,8 @@ ____________________________________________________________________________-->
     <listitem>
 <!--==========================orignal english content==========================
      <para>
-      Any <command>SELECT</>, <command>INSERT</>, <command>UPDATE</>,
-      <command>DELETE</>, or <command>VALUES</> statement.
+      Any <command>SELECT</command>, <command>INSERT</command>, <command>UPDATE</command>,
+      <command>DELETE</command>, or <command>VALUES</command> statement.
      </para>
 ____________________________________________________________________________-->
      <para>
@@ -203,7 +203,7 @@ ____________________________________________________________________________-->
   </variablelist>
  </refsect1>
 
- <refsect1 id="SQL-PREPARE-notes">
+ <refsect1 id="sql-prepare-notes">
 <!--==========================orignal english content==========================
   <title>Notes</title>
 ____________________________________________________________________________-->
@@ -249,9 +249,9 @@ ____________________________________________________________________________-->
   <para>
    To examine the query plan <productname>PostgreSQL</productname> is using
    for a prepared statement, use <xref linkend="sql-explain">, e.g.
-   <command>EXPLAIN EXECUTE</>.
+   <command>EXPLAIN EXECUTE</command>.
    If a generic plan is in use, it will contain parameter symbols
-   <literal>$<replaceable>n</></literal>, while a custom plan will have the
+   <literal>$<replaceable>n</replaceable></literal>, while a custom plan will have the
    supplied parameter values substituted into it.
    The row estimates in the generic plan reflect the selectivity
    computed for the parameters.
@@ -276,21 +276,21 @@ ____________________________________________________________________________-->
 <!--==========================orignal english content==========================
   <para>
    Although the main point of a prepared statement is to avoid repeated parse
-   analysis and planning of the statement, <productname>PostgreSQL</> will
+   analysis and planning of the statement, <productname>PostgreSQL</productname> will
    force re-analysis and re-planning of the statement before using it
    whenever database objects used in the statement have undergone
    definitional (DDL) changes since the previous use of the prepared
    statement.  Also, if the value of <xref linkend="guc-search-path"> changes
    from one use to the next, the statement will be re-parsed using the new
-   <varname>search_path</>.  (This latter behavior is new as of
+   <varname>search_path</varname>.  (This latter behavior is new as of
    <productname>PostgreSQL</productname> 9.3.)  These rules make use of a
    prepared statement semantically almost equivalent to re-submitting the
    same query text over and over, but with a performance benefit if no object
    definitions are changed, especially if the best plan remains the same
    across uses.  An example of a case where the semantic equivalence is not
    perfect is that if the statement refers to a table by an unqualified name,
    and then a new table of the same name is created in a schema appearing
-   earlier in the <varname>search_path</>, no automatic re-parse will occur
+   earlier in the <varname>search_path</varname>, no automatic re-parse will occur
    since no object used in the statement changed.  However, if some other
    change forces a re-parse, the new table will be referenced in subsequent
    uses.
@@ -349,7 +349,7 @@ EXECUTE usrrptplan(1, current_date);
 </programlisting>
 
    Note that the data type of the second parameter is not specified,
-   so it is inferred from the context in which <literal>$2</> is used.
+   so it is inferred from the context in which <literal>$2</literal> is used.
   </para>
 ____________________________________________________________________________-->
   <para>