diff options
| author | Tom Lane | 2014-02-14 17:54:43 +0000 |
|---|---|---|
| committer | Tom Lane | 2014-02-14 17:54:43 +0000 |
| commit | 6cafc4fb09bc3bc56365c5f76f1ceba11ec86088 (patch) | |
| tree | 0528cea12cb71a8e2694edb3ec2a6f79ab5e8936 | |
| parent | 762bd379a70d626b93d85d89772e47cc355041b3 (diff) | |
Suggest shell here-documents instead of psql -c for multiple commands.
The documentation suggested using "echo | psql", but not the often-superior
alternative of a here-document. Also, be more direct about suggesting
that people avoid -c for multiple commands. Per discussion.
| -rw-r--r-- | doc/src/sgml/ref/psql-ref.sgml | 20 |
1 files changed, 17 insertions, 3 deletions
diff --git a/doc/src/sgml/ref/psql-ref.sgml b/doc/src/sgml/ref/psql-ref.sgml index 5ad84381aba..f9680fca278 100644 --- a/doc/src/sgml/ref/psql-ref.sgml +++ b/doc/src/sgml/ref/psql-ref.sgml @@ -83,14 +83,15 @@ PostgreSQL documentation (<filename>psqlrc</filename> and <filename>~/.psqlrc</filename>) are ignored with this option. </para> - <para><replaceable class="parameter">command</replaceable> must be either + <para> + <replaceable class="parameter">command</replaceable> must be either a command string that is completely parsable by the server (i.e., it contains no <application>psql</application>-specific features), or a single backslash command. Thus you cannot mix <acronym>SQL</acronym> and <application>psql</application> meta-commands with this option. To achieve that, you could - pipe the string into <application>psql</application>, like - this: <literal>echo '\x \\ SELECT * FROM foo;' | psql</literal>. + pipe the string into <application>psql</application>, for example: + <literal>echo '\x \\ SELECT * FROM foo;' | psql</literal>. (<literal>\\</> is the separator meta-command.) </para> <para> @@ -102,6 +103,19 @@ PostgreSQL documentation <application>psql</application>'s standard input. Also, only the result of the last SQL command is returned. </para> + <para> + Because of these legacy behaviors, putting more than one command in + the <option>-c</option> string often has unexpected results. It's + better to feed multiple commands to <application>psql</application>'s + standard input, either using <application>echo</application> as + illustrated above, or via a shell here-document, for example: +<programlisting> +psql <<EOF +\x +SELECT * FROM foo; +EOF +</programlisting> + </para> </listitem> </varlistentry> |