To: Thomas Lockhart <Thomas.G.Lockhart@jpl.nasa.gov>

Subject: Re: [PATCHES] SET DateStyle patches

On Tue, 22 Apr 1997, Thomas Lockhart wrote:

> Some more patches! These (try to) finish implementing SET variable TO value
> for "DateStyle" (changed the name from simply "date" to be more descriptive).
> This is based on code from Martin and Bruce (?), which was easy to modify.
> The syntax is
>
> SET DateStyle TO 'iso'
> SET DateStyle TO 'postgres'
> SET DateStyle TO 'sql'
> SET DateStyle TO 'european'
> SET DateStyle TO 'noneuropean'
> SET DateStyle TO 'us'         (same as "noneuropean")
> SET DateStyle TO 'default'    (current same as "postgres,us")
>
> ("european" is just compared for the first 4 characters, and "noneuropean"
> is compared for the first 7 to allow less typing).
>
> Multiple arguments are allowed, so SET datestyle TO 'sql,euro' is valid.
>
> My mods also try to implement "SHOW variable" and "RESET variable", but
> that part just core dumps at the moment. I would guess that my errors
> are obvious to someone who knows what they are doing with the parser stuff,
> so if someone (Bruce and/or Martin??) could have it do the right thing
> we will have a more complete set of what we need.
>
> Also, I would like to have a floating point precision global variable to
> implement "SET precision TO 10" and perhaps "SET precision TO 10,2" for
> float8 and float4, but I don't know how to do that for integer types rather
> than strings. If someone is fixing the SHOW and RESET code, perhaps they can
> add some hooks for me to do the floats while they are at it.
>
> I've left some remnants of variable structures in the source code which
> I did not use in the interests of getting something working for v6.1.
> We'll have time to clean things up for the next release...

src/backend/parser/gram.y

@@ -10,7 +10,7 @@
  *
  *
  * IDENTIFICATION
- *    $Header: /cvsroot/pgsql/src/backend/parser/gram.y,v 1.30 1997/04/05 06:25:59 vadim Exp $
+ *    $Header: /cvsroot/pgsql/src/backend/parser/gram.y,v 1.31 1997/04/23 03:17:00 scrappy Exp $
  *
  * HISTORY
  *    AUTHOR		DATE		MAJOR EVENT
@@ -108,7 +108,7 @@ static Node *makeA_Expr(int oper, char *opname, Node *lexpr, Node *rexpr);
         RevokeStmt, RuleStmt, TransactionStmt, ViewStmt, LoadStmt,
 	CreatedbStmt, DestroydbStmt, VacuumStmt, RetrieveStmt, CursorStmt,
 	ReplaceStmt, AppendStmt, NotifyStmt, DeleteStmt, ClusterStmt,
-	ExplainStmt, VariableSetStmt
+	ExplainStmt, VariableSetStmt, VariableShowStmt, VariableResetStmt
 
 %type <str>	relation_name, copy_file_name, copy_delimiter, def_name,
 	database_name, access_method_clause, access_method, attr_name,
@@ -190,8 +190,8 @@ static Node *makeA_Expr(int oper, char *opname, Node *lexpr, Node *rexpr);
 	NONE, NOT, NOTHING, NOTIFY, NOTNULL, 
         OIDS, ON, OPERATOR, OPTION, OR, ORDER, 
         PNULL, PRIVILEGES, PUBLIC, PURGE, P_TYPE, 
-        RENAME, REPLACE, RETRIEVE, RETURNS, REVOKE, ROLLBACK, RULE, 
-        SELECT, SET, SETOF, STDIN, STDOUT, STORE, 
+        RENAME, REPLACE, RESET, RETRIEVE, RETURNS, REVOKE, ROLLBACK, RULE, 
+        SELECT, SET, SETOF, SHOW, STDIN, STDOUT, STORE, 
 	TABLE, TO, TRANSACTION, UNIQUE, UPDATE, USING, VACUUM, VALUES
 	VERBOSE, VERSION, VIEW, WHERE, WITH, WORK
 %token	EXECUTE, RECIPE, EXPLAIN, LIKE, SEQUENCE
@@ -275,6 +275,8 @@ stmt :	  AddAttrStmt
 	| DestroydbStmt
 	| VacuumStmt
 	| VariableSetStmt
+	| VariableShowStmt
+	| VariableResetStmt
 	;
 
 /*****************************************************************************
@@ -289,7 +291,7 @@ VariableSetStmt: SET var_name TO var_value
 		VariableSetStmt *n = makeNode(VariableSetStmt);
 		n->name  = $2;
 		n->value = $4;
-		
+
 		$$ = (Node *) n;
 		}
 	;
@@ -297,6 +299,26 @@ VariableSetStmt: SET var_name TO var_value
 var_value:	Sconst		{ $$ = $1; }
 	;
 
+VariableShowStmt: SHOW var_name
+		{
+		VariableSetStmt *n = makeNode(VariableSetStmt);
+		n->name  = $2;
+		n->value = NULL;
+
+		$$ = (Node *) n;
+		}
+	;
+
+VariableResetStmt: RESET var_name
+		{
+		VariableSetStmt *n = makeNode(VariableSetStmt);
+		n->name  = $2;
+		n->value = NULL;
+		
+		$$ = (Node *) n;
+		}
+	;
+
 /*****************************************************************************
  *
  *	QUERY :

src/backend/parser/keywords.c

@@ -7,7 +7,7 @@
  *
  *
  * IDENTIFICATION
- *    $Header: /cvsroot/pgsql/src/backend/parser/keywords.c,v 1.8 1997/04/02 04:49:13 vadim Exp $
+ *    $Header: /cvsroot/pgsql/src/backend/parser/keywords.c,v 1.9 1997/04/23 03:17:04 scrappy Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -116,6 +116,7 @@ static ScanKeyword ScanKeywords[] = {
 	{ "recipe",             RECIPE          },
 	{ "rename",		RENAME		},
 	{ "replace",		REPLACE		},
+	{ "reset",		RESET		},
 	{ "retrieve",		RETRIEVE	},
 	{ "returns",		RETURNS		},
         { "revoke",             REVOKE          },
@@ -125,6 +126,7 @@ static ScanKeyword ScanKeywords[] = {
 	{ "sequence",		SEQUENCE	},
 	{ "set",		SET		},
 	{ "setof",		SETOF		},
+	{ "show",		SHOW		},
 	{ "stdin",		STDIN		},
 	{ "stdout",		STDOUT		},
 	{ "store",		STORE		},