doc: Improve search_path mentions in index

Karl O. Pinc

doc/src/sgml/ddl.sgml

@@ -1735,7 +1735,7 @@ CREATE TABLE public.products ( ... );
    </para>
 
    <indexterm>
-    <primary>search_path</primary>
+    <primary><varname>search_path</varname> configuration parameter</primary>
    </indexterm>
 
    <para>

doc/src/sgml/func.sgml

@@ -13507,6 +13507,11 @@ SELECT relname FROM pg_class WHERE pg_table_is_visible(oid);
 </programlisting>
   </para>
 
+   <indexterm>
+    <primary>search path</primary>
+    <secondary>object visibility</secondary>
+   </indexterm>
+
    <table id="functions-info-schema-table">
     <title>Schema Visibility Inquiry Functions</title>
     <tgroup cols="3">

doc/src/sgml/ref/create_function.sgml

@@ -673,6 +673,11 @@ SELECT * FROM dup(42);
  <refsect1 id="sql-createfunction-security">
   <title>Writing <literal>SECURITY DEFINER</literal> Functions Safely</title>
 
+  <indexterm>
+   <primary><varname>search_path</varname> configuration parameter</>
+   <secondary>use in securing functions</>
+  </indexterm>
+
    <para>
     Because a <literal>SECURITY DEFINER</literal> function is executed
     with the privileges of the user that created it, care is needed to