diff --git a/doc/src/sgml/ref/prepare.sgml b/doc/src/sgml/ref/prepare.sgml
new file mode 100644
index dbce8f2..fce6e96
*** a/doc/src/sgml/ref/prepare.sgml
--- b/doc/src/sgml/ref/prepare.sgml
*************** PREPARE <replaceable class="PARAMETER">n
*** 127,140 ****
    <title>Notes</title>
  
    <para>
!    If a prepared statement is executed enough times, the server may eventually
!    decide to save and re-use a generic plan rather than re-planning each time.
!    This will occur immediately if the prepared statement has no parameters;
!    otherwise it occurs only if the generic plan appears to be not much more
!    expensive than a plan that depends on specific parameter values.
!    Typically, a generic plan will be selected only if the query's performance
!    is estimated to be fairly insensitive to the specific parameter values
!    supplied.
    </para>
  
    <para>
--- 127,147 ----
    <title>Notes</title>
  
    <para>
!    Prepared statements can optionally use generic plans rather than
!    re-planning with each set of supplied <command>EXECUTE</command> values.
!    This occurs immediately for prepared statements with no parameters;
!    otherwise it occurs only after five or more executions produce plans
!    plus planning costs that are, on average, cheaper than the generic plan.
!    A generic plan assumes each value supplied to <command>EXECUTE</command>
!    is one of the column's distinct values and that column values are
!    uniformly distributed.  For example, if statistics records three
!    distinct column values, a generic plan assumes a column equality
!    comparison will match 33% of processed rows.  Column statistics
!    also allows generic plans to accurately compute the selectivity of
!    unique columns.  Comparisons on non-uniformly-distributed columns and
!    specification of non-existent values affects the average plan cost,
!    and hence if and when a generic plan is chosen.  Once a generic plan is
!    chosen, it is used for the remaining lifetime of the prepared statement.
    </para>
  
    <para>
*************** PREPARE <replaceable class="PARAMETER">n
*** 142,148 ****
     for a prepared statement, use <xref linkend="sql-explain">.
     If a generic plan is in use, it will contain parameter symbols
     <literal>$<replaceable>n</></literal>, while a custom plan will have the
!    current actual parameter values substituted into it.
    </para>
  
    <para>
--- 149,157 ----
     for a prepared statement, use <xref linkend="sql-explain">.
     If a generic plan is in use, it will contain parameter symbols
     <literal>$<replaceable>n</></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.
    </para>
  
    <para>