Add pretty-printing variants of pg_get_viewdef and related functions.

Patch from Andreas Pflug.

doc/src/sgml/func.sgml

 <!--
-$Header: /cvsroot/pgsql/doc/src/sgml/func.sgml,v 1.161 2003/07/29 00:03:17 tgl Exp $
+$Header: /cvsroot/pgsql/doc/src/sgml/func.sgml,v 1.162 2003/07/30 22:56:23 tgl Exp $
 PostgreSQL documentation
 -->
 
@@ -6494,10 +6494,9 @@ SET search_path TO <replaceable>schema</> <optional>, <replaceable>schema</>, ..
 
    <para>
     The function <function>current_setting</function> yields the
-    current value of the setting <parameter>setting_name</parameter>,
-    as part of a query result. It corresponds to the
-    <acronym>SQL</acronym> command <command>SHOW</command>.  An
-    example:
+    current value of the setting <parameter>setting_name</parameter>.
+    It corresponds to the <acronym>SQL</acronym> command
+    <command>SHOW</command>.  An example:
 <programlisting>
 SELECT current_setting('datestyle');
 
@@ -6832,6 +6831,10 @@ SELECT pg_type_is_visible('myschema.widget'::regtype);
     <primary>pg_get_constraintdef</primary>
    </indexterm>
 
+   <indexterm zone="functions-misc">
+    <primary>pg_get_expr</primary>
+   </indexterm>
+
    <indexterm zone="functions-misc">
     <primary>pg_get_userbyid</primary>
    </indexterm>
@@ -6846,7 +6849,16 @@ SELECT pg_type_is_visible('myschema.widget'::regtype);
    <function>pg_get_constraintdef</function> respectively
    reconstruct the creating command for a view, rule, index, or
    constraint.  (Note that this is a decompiled reconstruction, not
-   the verbatim text of the command.)
+   the original text of the command.)  Most of these come in two
+   variants, one of which can optionally <quote>pretty-print</> the result.
+   The pretty-printed form is more readable but is less likely to be
+   interpreted the same way by future versions of <productname>PostgreSQL</>;
+   avoid using pretty-printed output for dump purposes.
+   Passing <literal>false</> for the pretty-print parameter yields the
+   same result as the variant that does not have the parameter at all.
+   <function>pg_get_expr</function> decompiles the internal form of an
+   individual expression, such as the default value for a column.  It
+   may be useful when examining the contents of system catalogs.
    <function>pg_get_userbyid</function>
    extracts a user's name given a user ID number.
   </para>
@@ -6864,21 +6876,43 @@ SELECT pg_type_is_visible('myschema.widget'::regtype);
        <entry><type>text</type></entry>
        <entry>get <command>CREATE VIEW</> command for view (<emphasis>deprecated</emphasis>)</entry>
       </row>
+      <row>
+       <entry><literal><function>pg_get_viewdef</function>(<parameter>view_name</parameter>, <parameter>pretty_bool</>)</literal></entry>
+       <entry><type>text</type></entry>
+       <entry>get <command>CREATE VIEW</> command for view (<emphasis>deprecated</emphasis>)</entry>
+      </row>
       <row>
        <entry><literal><function>pg_get_viewdef</function>(<parameter>view_oid</parameter>)</literal></entry>
        <entry><type>text</type></entry>
        <entry>get <command>CREATE VIEW</> command for view</entry>
       </row>
+      <row>
+       <entry><literal><function>pg_get_viewdef</function>(<parameter>view_oid</parameter>, <parameter>pretty_bool</>)</literal></entry>
+       <entry><type>text</type></entry>
+       <entry>get <command>CREATE VIEW</> command for view</entry>
+      </row>
       <row>
        <entry><literal><function>pg_get_ruledef</function>(<parameter>rule_oid</parameter>)</literal></entry>
        <entry><type>text</type></entry>
        <entry>get <command>CREATE RULE</> command for rule</entry>
       </row>
+      <row>
+       <entry><literal><function>pg_get_ruledef</function>(<parameter>rule_oid</parameter>, <parameter>pretty_bool</>)</literal></entry>
+       <entry><type>text</type></entry>
+       <entry>get <command>CREATE RULE</> command for rule</entry>
+      </row>
       <row>
        <entry><literal><function>pg_get_indexdef</function>(<parameter>index_oid</parameter>)</literal></entry>
        <entry><type>text</type></entry>
        <entry>get <command>CREATE INDEX</> command for index</entry>
       </row>
+      <row>
+       <entry><literal><function>pg_get_indexdef</function>(<parameter>index_oid</parameter>, <parameter>column_no</>, <parameter>pretty_bool</>)</literal></entry>
+       <entry><type>text</type></entry>
+       <entry>get <command>CREATE INDEX</> command for index,
+       or definition of just one index column when
+       <parameter>column_no</> is not zero</entry>
+      </row>
       <row>
        <entry><function>pg_get_triggerdef</function>(<parameter>trigger_oid</parameter>)</entry>
        <entry><type>text</type></entry>
@@ -6889,6 +6923,23 @@ SELECT pg_type_is_visible('myschema.widget'::regtype);
        <entry><type>text</type></entry>
        <entry>get definition of a constraint</entry>
       </row>
+      <row>
+       <entry><literal><function>pg_get_constraintdef</function>(<parameter>constraint_oid</parameter>, <parameter>pretty_bool</>)</literal></entry>
+       <entry><type>text</type></entry>
+       <entry>get definition of a constraint</entry>
+      </row>
+      <row>
+       <entry><literal><function>pg_get_expr</function>(<parameter>expr_text</parameter>, <parameter>relation_oid</>)</literal></entry>
+       <entry><type>text</type></entry>
+       <entry>decompile internal form of an expression, assuming that any Vars
+       in it refer to the relation indicated by the second parameter</entry>
+      </row>
+      <row>
+       <entry><literal><function>pg_get_expr</function>(<parameter>expr_text</parameter>, <parameter>relation_oid</>, <parameter>pretty_bool</>)</literal></entry>
+       <entry><type>text</type></entry>
+       <entry>decompile internal form of an expression, assuming that any Vars
+       in it refer to the relation indicated by the second parameter</entry>
+      </row>
       <row>
        <entry><literal><function>pg_get_userbyid</function>(<parameter>userid</parameter>)</literal></entry>
        <entry><type>name</type></entry>

src/include/catalog/catversion.h

@@ -37,7 +37,7 @@
  * Portions Copyright (c) 1996-2002, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $Id: catversion.h,v 1.203 2003/07/29 17:21:27 tgl Exp $
+ * $Id: catversion.h,v 1.204 2003/07/30 22:56:24 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -53,6 +53,6 @@
  */
 
 /*							yyyymmddN */
-#define CATALOG_VERSION_NO	200307291
+#define CATALOG_VERSION_NO	200307301
 
 #endif

src/include/catalog/pg_proc.h

@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1996-2002, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $Id: pg_proc.h,v 1.309 2003/07/01 00:04:38 tgl Exp $
+ * $Id: pg_proc.h,v 1.310 2003/07/30 22:56:24 tgl Exp $
  *
  * NOTES
  *	  The script catalog/genbki.sh reads this file and generates .bki
@@ -3405,6 +3405,20 @@ DESCR("I/O");
 DATA(insert OID = 2503 (  anyarray_send		   PGNSP PGUID 12 f f t f s 1 17 "2277"  anyarray_send - _null_ ));
 DESCR("I/O");
 
+/* System-view support functions with pretty-print option */
+DATA(insert OID = 2504 (  pg_get_ruledef	   PGNSP PGUID 12 f f t f s 2 25 "26 16"  pg_get_ruledef_ext - _null_ ));
+DESCR("source text of a rule with pretty-print option");
+DATA(insert OID = 2505 (  pg_get_viewdef	   PGNSP PGUID 12 f f t f s 2 25 "25 16"  pg_get_viewdef_name_ext - _null_ ));
+DESCR("select statement of a view with pretty-print option");
+DATA(insert OID = 2506 (  pg_get_viewdef	   PGNSP PGUID 12 f f t f s 2 25 "26 16"  pg_get_viewdef_ext - _null_ ));
+DESCR("select statement of a view with pretty-print option");
+DATA(insert OID = 2507 (  pg_get_indexdef	   PGNSP PGUID 12 f f t f s 3 25 "26 23 16"  pg_get_indexdef_ext - _null_ ));
+DESCR("index description (full create statement or single expression) with pretty-print option");
+DATA(insert OID = 2508 (  pg_get_constraintdef PGNSP PGUID 12 f f t f s 2 25 "26 16"  pg_get_constraintdef_ext - _null_ ));
+DESCR("constraint description with pretty-print option");
+DATA(insert OID = 2509 (  pg_get_expr		   PGNSP PGUID 12 f f t f s 3 25 "25 26 16"	pg_get_expr_ext - _null_ ));
+DESCR("deparse an encoded expression with pretty-print option");
+
 
 /*
  * Symbolic values for provolatile column: these indicate whether the result

src/include/utils/builtins.h

@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1996-2002, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $Id: builtins.h,v 1.223 2003/06/27 00:33:26 tgl Exp $
+ * $Id: builtins.h,v 1.224 2003/07/30 22:56:24 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -441,13 +441,19 @@ extern char *format_operator(Oid operator_oid);
 
 /* ruleutils.c */
 extern Datum pg_get_ruledef(PG_FUNCTION_ARGS);
+extern Datum pg_get_ruledef_ext(PG_FUNCTION_ARGS);
 extern Datum pg_get_viewdef(PG_FUNCTION_ARGS);
+extern Datum pg_get_viewdef_ext(PG_FUNCTION_ARGS);
 extern Datum pg_get_viewdef_name(PG_FUNCTION_ARGS);
+extern Datum pg_get_viewdef_name_ext(PG_FUNCTION_ARGS);
 extern Datum pg_get_indexdef(PG_FUNCTION_ARGS);
+extern Datum pg_get_indexdef_ext(PG_FUNCTION_ARGS);
 extern Datum pg_get_triggerdef(PG_FUNCTION_ARGS);
 extern Datum pg_get_constraintdef(PG_FUNCTION_ARGS);
+extern Datum pg_get_constraintdef_ext(PG_FUNCTION_ARGS);
 extern Datum pg_get_userbyid(PG_FUNCTION_ARGS);
 extern Datum pg_get_expr(PG_FUNCTION_ARGS);
+extern Datum pg_get_expr_ext(PG_FUNCTION_ARGS);
 extern char *deparse_expression(Node *expr, List *dpcontext,
 				   bool forceprefix, bool showimplicit);
 extern List *deparse_context_for(const char *aliasname, Oid relid);