I attached a updated patch including fixes you pointed out above.
Removed "which"; changed "occupying" to "occupy"
Removed on of the two "amounts"
Changed "unacceptable to the input function" to just "converting" as that is what the average reader is more likely to be thinking.
The rest was good.
diff --git a/doc/src/sgml/ref/copy.sgml b/doc/src/sgml/ref/copy.sgml index 3c2feaa11a..55764fc1f2 100644 --- a/doc/src/sgml/ref/copy.sgml +++ b/doc/src/sgml/ref/copy.sgml @@ -385,8 +385,8 @@ COPY { <replaceable class="parameter">table_name</replaceable> [ ( <replaceable <term><literal>ON_ERROR</literal></term> <listitem> <para> - Specifies which how to behave when encountering an error due to column values - unacceptable to the input function of each attribute's data type. + Specifies how to behave when encountering an error converting a column's + input value into its data type. An <replaceable class="parameter">error_action</replaceable> value of <literal>stop</literal> means fail the command, while <literal>ignore</literal> means discard the input row and continue with the next one. @@ -589,7 +589,7 @@ COPY <replaceable class="parameter">count</replaceable> The <command>COPY FROM</command> command physically inserts input rows into the table as it progresses. If the command fails, these rows are left in a deleted state; these rows will not be visible, but still - occupying disk space. This might amount to a considerable amount of + occupy disk space. This might amount to considerable wasted disk space if the failure happened well into a large copy operation. <command>VACUUM</command> should be used to recover the wasted space.