Remove vestigial grammar support for CHARACTER ... CHARACTER SET option.

tglsfdc · tglsfdc · commit 11324e408f0e · 2017-03-07T10:42:18.000-05:00
The SQL standard says that you should be able to write "CHARACTER SET foo" as part of the declaration of a char-type column. We don't implement that, but a rough form of support has existed in gram.y since commit f10b639. That's now sat there for nigh 20 years without anyone fleshing it out --- and even if someone did, the contemplated approach of having separate data type name(s) for every character set certainly isn't what we'd do today. Let's just remove the grammar production; if anyone is ever motivated to work on this, reinventing the grammar support is a trivial fraction of what they'd have to do. And we've never documented anything about supporting such a clause. Per gripe from Neha Khatri. Discussion: https://postgr.es/m/CAFO0U+-iOS5oYN5v3SBuZvfhPUTRrkDFEx8w7H17B07Rwg3YUA@mail.gmail.com
diff --git a/src/backend/parser/gram.y b/src/backend/parser/gram.y
@@ -513,7 +513,6 @@ static Node *makeRecursiveViewSelect(char *relname, List *aliases, Node *query);
 				Bit ConstBit BitWithLength BitWithoutLength
 %type <str>		character
 %type <str>		extract_arg
-%type <str>		opt_charset
 %type <boolean> opt_varying opt_timezone opt_no_inherit
 
 %type <ival>	Iconst SignedIconst
@@ -11923,28 +11922,20 @@ ConstCharacter:  CharacterWithLength
 				}
 		;
 
-CharacterWithLength:  character '(' Iconst ')' opt_charset
+CharacterWithLength:  character '(' Iconst ')'
 				{
-					if (($5 != NULL) && (strcmp($5, "sql_text") != 0))
-						$1 = psprintf("%s_%s", $1, $5);
-
 					$$ = SystemTypeName($1);
 					$$->typmods = list_make1(makeIntConst($3, @3));
 					$$->location = @1;
 				}
 		;
 
-CharacterWithoutLength:	 character opt_charset
+CharacterWithoutLength:	 character
 				{
-					if (($2 != NULL) && (strcmp($2, "sql_text") != 0))
-						$1 = psprintf("%s_%s", $1, $2);
-
 					$$ = SystemTypeName($1);
-
 					/* char defaults to char(1), varchar to no limit */
 					if (strcmp($1, "bpchar") == 0)
 						$$->typmods = list_make1(makeIntConst(1, -1));
-
 					$$->location = @1;
 				}
 		;
@@ -11968,11 +11959,6 @@ opt_varying:
 			| /*EMPTY*/								{ $$ = FALSE; }
 		;
 
-opt_charset:
-			CHARACTER SET ColId						{ $$ = $3; }
-			| /*EMPTY*/								{ $$ = NULL; }
-		;
-
 /*
  * SQL date/time types
  */

Original file line number	Diff line number	Diff line change
`@@ -513,7 +513,6 @@ static Node makeRecursiveViewSelect(char relname, List aliases, Node query);`
`513`	`513`	`Bit ConstBit BitWithLength BitWithoutLength`
`514`	`514`	`%type <str> character`
`515`	`515`	`%type <str> extract_arg`
`516`		`-%type <str> opt_charset`
`517`	`516`	`%type <boolean> opt_varying opt_timezone opt_no_inherit`
`518`	`517`
`519`	`518`	`%type <ival> Iconst SignedIconst`
`@@ -11923,28 +11922,20 @@ ConstCharacter: CharacterWithLength`
`11923`	`11922`	`}`
`11924`	`11923`	`;`
`11925`	`11924`
`11926`		`-CharacterWithLength: character '(' Iconst ')' opt_charset`
	`11925`	`+CharacterWithLength: character '(' Iconst ')'`
`11927`	`11926`	`{`
`11928`		`- if (($5 != NULL) && (strcmp($5, "sql_text") != 0))`
`11929`		`- $1 = psprintf("%s_%s", $1, $5);`
`11930`		`-`
`11931`	`11927`	`$$ = SystemTypeName($1);`
`11932`	`11928`	`$$->typmods = list_make1(makeIntConst($3, @3));`
`11933`	`11929`	`$$->location = @1;`
`11934`	`11930`	`}`
`11935`	`11931`	`;`
`11936`	`11932`
`11937`		`-CharacterWithoutLength: character opt_charset`
	`11933`	`+CharacterWithoutLength: character`
`11938`	`11934`	`{`
`11939`		`- if (($2 != NULL) && (strcmp($2, "sql_text") != 0))`
`11940`		`- $1 = psprintf("%s_%s", $1, $2);`
`11941`		`-`
`11942`	`11935`	`$$ = SystemTypeName($1);`
`11943`		`-`
`11944`	`11936`	`/* char defaults to char(1), varchar to no limit */`
`11945`	`11937`	`if (strcmp($1, "bpchar") == 0)`
`11946`	`11938`	`$$->typmods = list_make1(makeIntConst(1, -1));`
`11947`		`-`
`11948`	`11939`	`$$->location = @1;`
`11949`	`11940`	`}`
`11950`	`11941`	`;`
`@@ -11968,11 +11959,6 @@ opt_varying:`
`11968`	`11959`	`\| /EMPTY/ { $$ = FALSE; }`
`11969`	`11960`	`;`
`11970`	`11961`
`11971`		`-opt_charset:`
`11972`		`- CHARACTER SET ColId { $$ = $3; }`
`11973`		`- \| /EMPTY/ { $$ = NULL; }`
`11974`		`- ;`
`11975`		`-`
`11976`	`11962`	`/*`
`11977`	`11963`	`* SQL date/time types`
`11978`	`11964`	`*/`