Make SET SESSION CHARACTERISTICS compliant with SQL 99. Remove redundant,

non-standard clauses.  Allow CHARACTERISTICS as unquoted identifier.
Merge related reference pages.

doc/src/sgml/ref/allfiles.sgml

 <!--
-$Header: /cvsroot/pgsql/doc/src/sgml/ref/allfiles.sgml,v 1.25 2000/11/24 17:44:22 petere Exp $
+$Header: /cvsroot/pgsql/doc/src/sgml/ref/allfiles.sgml,v 1.26 2000/11/24 20:16:38 petere Exp $
 Postgres documentation
 Complete list of usable sgml source files in this directory.
 -->
@@ -95,7 +95,6 @@ Complete list of usable sgml source files in this directory.
 <!entity select             system "select.sgml">
 <!entity selectInto         system "select_into.sgml">
 <!entity set                system "set.sgml">
-<!entity setSession         system "set_session.sgml">
 <!entity setConstraints     system "set_constraints.sgml">
 <!entity setTransaction     system "set_transaction.sgml">
 <!entity show               system "show.sgml">

doc/src/sgml/ref/set_session.sgml

-<!--
-$Header: /cvsroot/pgsql/doc/src/sgml/ref/Attic/set_session.sgml,v 1.1 2000/07/14 15:27:14 thomas Exp $
-Postgres documentation
--->
-
-<refentry id="SQL-SET-SESSION">
- <refmeta>
-  <refentrytitle id="SQL-SET-SESSION-TITLE">SET</refentrytitle>
-  <refmiscinfo>SQL - Language Statements</refmiscinfo>
- </refmeta>
- <refnamediv>
-  <refname>SET SESSION CHARACTERISTICS</refname>
-  <refpurpose>Set per-session run-time parameters</refpurpose>
- </refnamediv>
- <refsynopsisdiv>
-  <synopsis>
-SET SESSION CHARACTERISTICS TRANSACTION ISOLATION LEVEL { READ COMMITTED | SERIALIZABLE }
-SET SESSION CHARACTERISTICS TIME ZONE { '<replaceable class="PARAMETER">timezone</replaceable>' | LOCAL | DEFAULT }
-  </synopsis>
- </refsynopsisdiv>
-
- <refsect1 id="R1-SQL-SET-SESSION-1">
-  <title>Description</title>
-  <para>
-   <command>SET SESSION CHARACTERISTICS</command> changes the run-time
-   environment for the entire <acronym>SQL</acronym>
-   session. Currently, transaction isolation level and time zone can
-   be specified by this command.
-  </para>
-
-  <para>
-   Use <xref linkend="SQL-SHOW" endterm="SQL-SHOW-title"> to show the
-   current setting of a parameters.
-  </para>
-
-  <para>
-   Refer to <xref linkend="SQL-SET-TRANSACTION" endterm="SQL-SET-TRANSACTION-TITLE">
-   and to <xref linkend="SQL-SET" endterm="SQL-SET-TITLE"> for more
-   information on allowed parameters.
-  </para>
- </refsect1>
-
- <refsect1>
-  <title>Examples</title>
-
-  <para>
-   Set the timezone for Berkeley, California, using double quotes to
-   preserve the uppercase attributes of the time zone specifier (note
-   that the date/time format is ISO here):
-
-<screen> 
-SET SESSION CHARACTERISTICS TIME ZONE "PST8PDT";
-SELECT CURRENT_TIMESTAMP AS today;
-   
-         today
-------------------------
- 1998-07-14 07:41:21-07
-</screen>
-  </para>
- </refsect1>
-
- <refsect1 id="R1-SQL-SET-SESSION-3">
-  <title>Compatibility</title>
-
-  <refsect2 id="R2-SQL-SET-SESSION-4">
-   <title>SQL99</title>
-
-   <para>
-    <command>SET SESSION</command> is defined in
-    <acronym>SQL99</acronym>.
-   </para>
-  </refsect2>
- </refsect1>
-</refentry>
-
-<!-- Keep this comment at the end of the file
-Local variables:
-mode:sgml
-sgml-omittag:nil
-sgml-shorttag:t
-sgml-minimize-attributes:nil
-sgml-always-quote-attributes:t
-sgml-indent-step:1
-sgml-indent-data:t
-sgml-parent-document:nil
-sgml-default-dtd-file:"../reference.ced"
-sgml-exposed-tags:nil
-sgml-local-catalogs:("/usr/lib/sgml/catalog")
-sgml-local-ecat-files:nil
-End:
--->

doc/src/sgml/ref/set_transaction.sgml

-<!-- $Header: /cvsroot/pgsql/doc/src/sgml/ref/set_transaction.sgml,v 1.2 2000/07/14 15:27:14 thomas Exp $ -->
+<!-- $Header: /cvsroot/pgsql/doc/src/sgml/ref/set_transaction.sgml,v 1.3 2000/11/24 20:16:38 petere Exp $ -->
 <refentry id="SQL-SET-TRANSACTION">
+ <docinfo>
+  <date>2000-11-24</date>
+ </docinfo>
+
  <refmeta>
   <refentrytitle id="SQL-SET-TRANSACTION-TITLE">SET TRANSACTION</refentrytitle>
   <refmiscinfo>SQL - Language Statements</refmiscinfo>
  </refmeta>
+
  <refnamediv>
   <refname>SET TRANSACTION</refname>
   <refpurpose>Set the characteristics of the current SQL-transaction</refpurpose>
  </refnamediv>
+
  <refsynopsisdiv>
-  <refsynopsisdivinfo>
-   <date>2000-06-01</date>
-  </refsynopsisdivinfo>
   <synopsis>
 SET TRANSACTION ISOLATION LEVEL { READ COMMITTED | SERIALIZABLE }
+SET SESSION CHARACTERISTICS AS TRANSACTION ISOLATION LEVEL { READ COMMITTED | SERIALIZABLE }
   </synopsis>
  </refsynopsisdiv>
 
@@ -21,13 +25,17 @@ SET TRANSACTION ISOLATION LEVEL { READ COMMITTED | SERIALIZABLE }
   <title>Description</title>
 
   <para>
-   The <command>SET TRANSACTION</command> command sets the
-   characteristics for the current SQL-transaction. It has no effect
-   on any subsequent transactions. This command cannot be used after
-   the first DML statement (<command>SELECT</command>,
-   <command>INSERT</command>, <command>DELETE</command>,
-   <command>UPDATE</command>, <command>FETCH</command>,
-   <command>COPY</command>) of a transaction has been executed.
+   This command sets the transaction isolation level.  The
+   <command>SET TRANSACTION</command> command sets the characteristics
+   for the current SQL-transaction. It has no effect on any subsequent
+   transactions.  This command cannot be used after the first DML
+   statement (<command>SELECT</command>, <command>INSERT</command>,
+   <command>DELETE</command>, <command>UPDATE</command>,
+   <command>FETCH</command>, <command>COPY</command>) of a transaction
+   has been executed.  <command>SET SESSION CHARACTERISTICS</command>
+   sets the default transaction isolation level for each transaction
+   for a session.  <command>SET TRANSACTION</command> can override it
+   for an individual transaction.
   </para>
 
   <para>
@@ -83,7 +91,7 @@ SET TRANSACTION ISOLATION LEVEL { READ COMMITTED | SERIALIZABLE }
 
    <para>
     In <acronym>SQL</acronym> there are two other transaction
-    characteristics that can be set with this command: whether the
+    characteristics that can be set with these commands: whether the
     transaction is read-only and the size of the diagnostics area.
     Neither of these concepts are supported in Postgres.
    </para>

src/backend/nodes/copyfuncs.c

@@ -15,7 +15,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/nodes/copyfuncs.c,v 1.132 2000/11/14 18:37:42 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/nodes/copyfuncs.c,v 1.133 2000/11/24 20:16:39 petere Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -2513,16 +2513,6 @@ _copyReindexStmt(ReindexStmt *from)
 	return newnode;
 }
 
-static SetSessionStmt *
-_copySetSessionStmt(SetSessionStmt *from)
-{
-	SetSessionStmt   *newnode = makeNode(SetSessionStmt);
-
-	Node_Copy(from, newnode, args);
-
-	return newnode;
-}
-
 
 /* ****************************************************************
  *					pg_list.h copy functions
@@ -2922,9 +2912,6 @@ copyObject(void *from)
 		case T_ReindexStmt:
 			retval = _copyReindexStmt(from);
 			break;
-		case T_SetSessionStmt:
-			retval = _copySetSessionStmt(from);
-			break;
 		case T_CheckPointStmt:
 			retval = (void*)makeNode(CheckPointStmt);
 			break;

src/backend/nodes/equalfuncs.c

@@ -20,7 +20,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/nodes/equalfuncs.c,v 1.82 2000/11/14 18:37:42 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/nodes/equalfuncs.c,v 1.83 2000/11/24 20:16:39 petere Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -1363,15 +1363,6 @@ _equalReindexStmt(ReindexStmt *a, ReindexStmt *b)
 	return true;
 }
 
-static bool
-_equalSetSessionStmt(SetSessionStmt *a, SetSessionStmt *b)
-{
-	if (!equal(a->args, b->args))
-		return false;
-
-	return true;
-}
-
 static bool
 _equalAExpr(A_Expr *a, A_Expr *b)
 {
@@ -2037,9 +2028,6 @@ equal(void *a, void *b)
 		case T_ReindexStmt:
 			retval = _equalReindexStmt(a, b);
 			break;
-		case T_SetSessionStmt:
-			retval = _equalSetSessionStmt(a, b);
-			break;
 		case T_CheckPointStmt:
 			retval = true;
 			break;

src/backend/parser/analyze.c

@@ -6,7 +6,7 @@
  * Portions Copyright (c) 1996-2000, PostgreSQL, Inc
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- *	$Id: analyze.c,v 1.167 2000/11/18 16:17:20 petere Exp $
+ *	$Id: analyze.c,v 1.168 2000/11/24 20:16:39 petere Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -208,38 +208,6 @@ transformStmt(ParseState *pstate, Node *parseTree)
 			result = transformAlterTableStmt(pstate, (AlterTableStmt *) parseTree);
 			break;
 
-		case T_SetSessionStmt:
-			{
-				List *l;
-				/* Session is a list of SetVariable nodes
-				 * so just run through the list.
-				 */
-				SetSessionStmt *stmt = (SetSessionStmt *) parseTree;
-
-				l = stmt->args;
-				/* First check for duplicate keywords (disallowed by SQL99) */
-				while (l != NULL)
-				{
-					VariableSetStmt *v = (VariableSetStmt *) lfirst(l);
-					List *ll = lnext(l);
-					while (ll != NULL)
-					{
-						VariableSetStmt *vv = (VariableSetStmt *) lfirst(ll);
-						if (strcmp(v->name, vv->name) == 0)
-							elog(ERROR, "SET SESSION CHARACTERISTICS duplicated entry not allowed");
-						ll = lnext(ll);
-					}
-					l = lnext(l);
-				}
-
-				l = stmt->args;
-				result = transformStmt(pstate, lfirst(l));
-				l = lnext(l);
-				if (l != NULL)
-					extras_after = lappend(extras_after, lfirst(l));
-			}
-			break;
-
 			/*------------------------
 			 *	Optimizable statements
 			 *------------------------

src/backend/parser/gram.y

@@ -11,7 +11,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/parser/gram.y,v 2.209 2000/11/14 18:37:49 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/parser/gram.y,v 2.210 2000/11/24 20:16:39 petere Exp $
  *
  * HISTORY
  *	  AUTHOR			DATE			MAJOR EVENT
@@ -134,15 +134,12 @@ static void doNegateFloat(Value *v);
 		NotifyStmt, OptimizableStmt, ProcedureStmt, ReindexStmt,
 		RemoveAggrStmt, RemoveFuncStmt, RemoveOperStmt,
 		RenameStmt, RevokeStmt, RuleActionStmt, RuleActionStmtOrEmpty,
-		RuleStmt, SelectStmt, SetSessionStmt, TransactionStmt, TruncateStmt,
+		RuleStmt, SelectStmt, TransactionStmt, TruncateStmt,
 		UnlistenStmt, UpdateStmt, VacuumStmt, VariableResetStmt,
 		VariableSetStmt, VariableShowStmt, ViewStmt, CheckPointStmt
 
 %type <node>	select_no_parens, select_clause, simple_select
 
-%type <list>	SessionList
-%type <node>	SessionClause
-
 %type <node>    alter_column_action
 %type <ival>    drop_behavior
 
@@ -459,7 +456,6 @@ stmt :	AlterSchemaStmt
 		| RevokeStmt
 		| OptimizableStmt
 		| RuleStmt
-		| SetSessionStmt
 		| TransactionStmt
 		| ViewStmt
 		| LoadStmt
@@ -706,55 +702,6 @@ DropSchemaStmt:  DROP SCHEMA UserId
 				}
 
 
-/*****************************************************************************
- *
- * Manipulate a postgresql session
- *
- *
- *****************************************************************************/
-
-SetSessionStmt:  SET SESSION CHARACTERISTICS AS SessionList
-				{
-					SetSessionStmt *n = makeNode(SetSessionStmt);
-					n->args = $5;
-					$$ = (Node*)n;
-				}
-		;
-
-SessionList:  SessionList ',' SessionClause
-				{
-					$$ = lappend($1, $3);
-				}
-		| SessionClause
-				{
-					$$ = makeList1($1);
-				}
-		;
-
-SessionClause:  TRANSACTION COMMIT opt_boolean
-				{
-					VariableSetStmt *n = makeNode(VariableSetStmt);
-					n->name  = "autocommit";
-					n->value = $3;
-					$$ = (Node *) n;
-				}
-		| TIME ZONE zone_value
-				{
-					VariableSetStmt *n = makeNode(VariableSetStmt);
-					n->name  = "timezone";
-					n->value = $3;
-					$$ = (Node *) n;
-				}
-		| TRANSACTION ISOLATION LEVEL opt_level
-				{
-					VariableSetStmt *n = makeNode(VariableSetStmt);
-					n->name  = "DefaultXactIsoLevel";
-					n->value = $4;
-					$$ = (Node *) n;
-				}
-			;
-
-
 /*****************************************************************************
  *
  * Set PG internal variable
@@ -792,6 +739,13 @@ VariableSetStmt:  SET ColId TO var_value
 					n->value = $5;
 					$$ = (Node *) n;
 				}
+        | SET SESSION CHARACTERISTICS AS TRANSACTION ISOLATION LEVEL opt_level
+				{
+					VariableSetStmt *n = makeNode(VariableSetStmt);
+					n->name  = "DefaultXactIsoLevel";
+					n->value = $8;
+					$$ = (Node *) n;
+				}
 		| SET NAMES opt_encoding
 				{
 					VariableSetStmt *n = makeNode(VariableSetStmt);
@@ -5444,6 +5398,7 @@ TokenId:  ABSOLUTE						{ $$ = "absolute"; }
 		| CACHE							{ $$ = "cache"; }
 		| CASCADE						{ $$ = "cascade"; }
 		| CHAIN							{ $$ = "chain"; }
+		| CHARACTERISTICS				{ $$ = "characteristics"; }
 		| CHECKPOINT					{ $$ = "checkpoint"; }
 		| CLOSE							{ $$ = "close"; }
 		| COMMENT						{ $$ = "comment"; }

src/include/nodes/nodes.h

@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1996-2000, PostgreSQL, Inc
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $Id: nodes.h,v 1.83 2000/11/12 00:37:01 tgl Exp $
+ * $Id: nodes.h,v 1.84 2000/11/24 20:16:40 petere Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -202,7 +202,6 @@ typedef enum NodeTag
 	T_AlterGroupStmt,
 	T_DropGroupStmt,
 	T_ReindexStmt,
-	T_SetSessionStmt,
 	T_CheckPointStmt,
 
 	T_A_Expr = 700,

src/include/nodes/parsenodes.h

@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1996-2000, PostgreSQL, Inc
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $Id: parsenodes.h,v 1.121 2000/11/14 18:37:48 tgl Exp $
+ * $Id: parsenodes.h,v 1.122 2000/11/24 20:16:40 petere Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -697,15 +697,9 @@ typedef struct ExplainStmt
 } ExplainStmt;
 
 /* ----------------------
- *		Set Session Statement
+ * Checkpoint Statement
  * ----------------------
  */
-typedef struct SetSessionStmt
-{
-	NodeTag		type;
-	List	   *args;
-} SetSessionStmt;
-
 typedef struct CheckPointStmt
 {
 	NodeTag		type;