diff options
| -rw-r--r-- | doc/src/sgml/ref/copy.sgml | 19 |
1 files changed, 9 insertions, 10 deletions
diff --git a/doc/src/sgml/ref/copy.sgml b/doc/src/sgml/ref/copy.sgml index 79ed7c204e3..b0e05188381 100644 --- a/doc/src/sgml/ref/copy.sgml +++ b/doc/src/sgml/ref/copy.sgml @@ -1,5 +1,5 @@ <!-- -$PostgreSQL: pgsql/doc/src/sgml/ref/copy.sgml,v 1.89 2009/09/17 21:49:15 momjian Exp $ +$PostgreSQL: pgsql/doc/src/sgml/ref/copy.sgml,v 1.90 2009/09/18 20:01:13 tgl Exp $ PostgreSQL documentation --> @@ -183,8 +183,8 @@ COPY { <replaceable class="parameter">tablename</replaceable> [ ( <replaceable c <listitem> <para> The string that represents a null value. The default is - <literal>\N</literal> (backslash-N) in text mode, and a empty - value with no quotes in <literal>CSV</> mode. You might prefer an + <literal>\N</literal> (backslash-N) in text mode, and an unquoted empty + string in <literal>CSV</> mode. You might prefer an empty string even in text mode for cases where you don't want to distinguish nulls from empty strings. </para> @@ -249,8 +249,7 @@ COPY { <replaceable class="parameter">tablename</replaceable> [ ( <replaceable c In <literal>CSV</> <command>COPY TO</> mode, forces quoting to be used for all non-<literal>NULL</> values in each specified column. <literal>NULL</> output is never quoted. If <literal>*</> is specified, - non-<literal>NULL</> values for all columns of the table will be - quoted. + non-<literal>NULL</> values will be quoted in all columns. </para> </listitem> </varlistentry> @@ -550,11 +549,11 @@ COPY <replaceable class="parameter">count</replaceable> <para> The <literal>CSV</> format has no standard way to distinguish a <literal>NULL</> value from an empty string. - <productname>PostgreSQL</>'s <command>COPY</> handles this by - quoting. A <literal>NULL</> is output as the <literal>NULL</> - parameter and is not quoted, while a non-NULL value matching the - the <literal>NULL</> parameter string is quoted. Therefore, using the default - settings, a <literal>NULL</> is written as an unquoted empty + <productname>PostgreSQL</>'s <command>COPY</> handles this by quoting. + A <literal>NULL</> is output as the <literal>NULL</> parameter string + and is not quoted, while a non-<literal>NULL</> value matching the + <literal>NULL</> parameter string is quoted. For example, with the + default settings, a <literal>NULL</> is written as an unquoted empty string, while an empty string data value is written with double quotes (<literal>""</>). Reading values follows similar rules. You can use <literal>FORCE NOT NULL</> to prevent <literal>NULL</> input |