SET NAMES has been extended to support optional collation:

SET NAMES <charset name> [COLLATE <collation name>]

mysql-test/r/ctype_collate.result

@@ -510,4 +510,22 @@ t1	CREATE TABLE `t1` (
 SHOW FIELDS FROM  t1;
 Field	Type	Collation	Null	Key	Default	Extra
 latin1_f	char(32)	latin1_bin	YES		NULL	
+SET NAMES 'latin1';
+SET NAMES latin1;
+SELECT charset('a'),collation('a'),coercibility('a'),'a'='A';
+charset('a')	collation('a')	coercibility('a')	'a'='A'
+latin1	latin1	2	1
+SET NAMES latin1 COLLATE latin1_bin;
+SET NAMES 'latin1' COLLATE 'latin1_bin';
+SELECT charset('a'),collation('a'),coercibility('a'),'a'='A';
+charset('a')	collation('a')	coercibility('a')	'a'='A'
+latin1	latin1_bin	2	0
+SET NAMES DEFAULT;
+SELECT charset('a'),collation('a'),coercibility('a'),'a'='A';
+charset('a')	collation('a')	coercibility('a')	'a'='A'
+latin1	latin1	2	1
+SET NAMES latin1 COLLATE koi8r;
+COLLATION 'koi8r' is not valid for CHARACTER SET 'latin1'
+SET NAMES 'DEFAULT';
+Unknown character set: 'DEFAULT'
 DROP TABLE t1;

mysql-test/t/ctype_collate.test

@@ -127,4 +127,18 @@ ALTER TABLE t1 CHARACTER SET latin1 COLLATE latin1_bin;
 SHOW CREATE TABLE t1;
 SHOW FIELDS FROM  t1;
 
+SET NAMES 'latin1';
+SET NAMES latin1;
+SELECT charset('a'),collation('a'),coercibility('a'),'a'='A';
+SET NAMES latin1 COLLATE latin1_bin;
+SET NAMES 'latin1' COLLATE 'latin1_bin';
+SELECT charset('a'),collation('a'),coercibility('a'),'a'='A';
+SET NAMES DEFAULT;
+SELECT charset('a'),collation('a'),coercibility('a'),'a'='A';
+--error 1251
+SET NAMES latin1 COLLATE koi8r;
+--error 1115
+SET NAMES 'DEFAULT';
+
+
 DROP TABLE t1;

sql/set_var.cc

@@ -104,7 +104,7 @@ sys_var_str		sys_charset("character_set",
 				    sys_check_charset,
 				    sys_update_charset,
 				    sys_set_default_charset);
-sys_var_thd_client_charset sys_client_charset("client_character_set");
+sys_var_client_collation sys_client_collation("client_collation");
 sys_var_thd_conv_charset sys_convert_charset("convert_character_set");
 sys_var_bool_ptr	sys_concurrent_insert("concurrent_insert",
 					      &myisam_concurrent_insert);
@@ -332,7 +332,7 @@ sys_var *sys_variables[]=
   &sys_binlog_cache_size,
   &sys_buffer_results,
   &sys_bulk_insert_buff_size,
-  &sys_client_charset,
+  &sys_client_collation,
   &sys_concurrent_insert,
   &sys_connect_timeout,
   &sys_convert_charset,
@@ -439,7 +439,7 @@ struct show_var_st init_vars[]= {
   {sys_bulk_insert_buff_size.name,(char*) &sys_bulk_insert_buff_size,SHOW_SYS},
   {sys_charset.name, 	      (char*) &sys_charset,		     SHOW_SYS},
   {"character_sets",          (char*) &charsets_list,               SHOW_CHAR_PTR},
-  {sys_client_charset.name,   (char*) &sys_client_charset,	    SHOW_SYS},
+  {sys_client_collation.name, (char*) &sys_client_collation,	    SHOW_SYS},
   {sys_concurrent_insert.name,(char*) &sys_concurrent_insert,       SHOW_SYS},
   {sys_connect_timeout.name,  (char*) &sys_connect_timeout,         SHOW_SYS},
   {sys_convert_charset.name,  (char*) &sys_convert_charset,	    SHOW_SYS},
@@ -1177,7 +1177,7 @@ byte *sys_var_thd_conv_charset::value_ptr(THD *thd, enum_var_type type)
 }
 
 
-bool sys_var_thd_client_charset::check(THD *thd, set_var *var)
+bool sys_var_client_collation::check(THD *thd, set_var *var)
 {
   CHARSET_INFO *tmp;
   char buff[80];
@@ -1187,14 +1187,14 @@ bool sys_var_thd_client_charset::check(THD *thd, set_var *var)
   {
     var->save_result.charset= (var->type != OPT_GLOBAL ?
 			       global_system_variables.thd_charset
-			       : default_charset_info);
+			       : thd->db_charset);
     return 0;
   }
 
   if (!(res=var->value->val_str(&str)))
     res= &empty_string;
 
-  if (!(tmp=get_charset_by_csname(res->c_ptr(),MY_CS_PRIMARY,MYF(0))))
+  if (!(tmp=get_charset_by_name(res->c_ptr(),MYF(0))))
   {
     my_error(ER_UNKNOWN_CHARACTER_SET, MYF(0), res->c_ptr());
     return 1;
@@ -1203,7 +1203,7 @@ bool sys_var_thd_client_charset::check(THD *thd, set_var *var)
   return 0;
 }
 
-bool sys_var_thd_client_charset::update(THD *thd, set_var *var)
+bool sys_var_client_collation::update(THD *thd, set_var *var)
 {
   if (var->type == OPT_GLOBAL)
     global_system_variables.thd_charset= var->save_result.charset;
@@ -1217,12 +1217,12 @@ bool sys_var_thd_client_charset::update(THD *thd, set_var *var)
 }
 
 
-byte *sys_var_thd_client_charset::value_ptr(THD *thd, enum_var_type type)
+byte *sys_var_client_collation::value_ptr(THD *thd, enum_var_type type)
 {
   CHARSET_INFO *cs= ((type == OPT_GLOBAL) ?
 		  global_system_variables.thd_charset :
 		  thd->variables.thd_charset);
-  return cs ? (byte*) cs->csname : (byte*) "";
+  return cs ? (byte*) cs->name : (byte*) "";
 }
 
 

sql/set_var.h

@@ -423,10 +423,10 @@ public:
   bool check_default(enum_var_type type) { return 0; }
 };
 
-class sys_var_thd_client_charset :public sys_var_thd
+class sys_var_client_collation :public sys_var_thd
 {
 public:
-  sys_var_thd_client_charset(const char *name_arg) :sys_var_thd(name_arg)
+  sys_var_client_collation(const char *name_arg) :sys_var_thd(name_arg)
   {}
   bool check(THD *thd, set_var *var);
   bool update(THD *thd, set_var *var);

sql/sql_yacc.yy

@@ -635,6 +635,7 @@ bool my_yyoverflow(short **a, YYSTYPE **b,int *yystacksize);
 %type <lex_user> user grant_user
 
 %type <charset>
+	opt_collate
 	charset_name
 	charset_name_or_default
 	collation_name
@@ -1302,7 +1303,7 @@ attribute:
 
 
 charset_name:
-	ident
+	ident_or_text
 	{
 	  if (!($$=get_charset_by_csname($1.str,MY_CS_PRIMARY,MYF(0))))
 	  {
@@ -1316,7 +1317,7 @@ charset_name_or_default:
 	| DEFAULT    { $$=NULL; } ;
 
 collation_name:
-	ident
+	ident_or_text
 	{
 	  if (!($$=get_charset_by_name($1.str,MYF(0))))
 	  {
@@ -1325,6 +1326,11 @@ collation_name:
 	  }
 	};
 
+opt_collate:
+	/* empty */	{ $$=NULL; }
+	| COLLATE_SYM collation_name { $$=$2; }
+	;
+
 collation_name_or_default:
 	collation_name { $$=$1;   }
 	| DEFAULT    { $$=NULL; } ;
@@ -1989,7 +1995,7 @@ expr_expr:
 	  { $$= new Item_date_add_interval($1,$3,$4,0); }
 	| expr '-' interval_expr interval
 	  { $$= new Item_date_add_interval($1,$3,$4,1); }
-	| expr COLLATE_SYM ident
+	| expr COLLATE_SYM ident_or_text
 	  { 
 	    $$= new Item_func_set_collation($1,new Item_string($3.str,$3.length,
 					    YYTHD->variables.thd_charset));
@@ -4216,12 +4222,26 @@ option_value:
 					      find_sys_var("convert_character_set"),
 					      $4));
 	}
-	| NAMES_SYM opt_equal set_expr_or_default
+	| NAMES_SYM charset_name_or_default opt_collate
 	{
-	  LEX *lex=Lex;
+	  THD* thd= YYTHD;
+	  LEX *lex= &thd->lex;
+	  system_variables vars= thd->variables;
+	  CHARSET_INFO *cs= $2 ? $2 : thd->db_charset;
+	  CHARSET_INFO *cl= $3 ? $3 : cs;
+
+	  if ((cl != cs) && strcmp(cs->csname,cl->csname))
+	  {
+	      net_printf(YYTHD,ER_COLLATION_CHARSET_MISMATCH, 
+		         cl->name,cs->csname);
+	      YYABORT;
+	  }
+	  Item_string *csname= new Item_string(cl->name, 
+					       strlen(cl->name), 
+					       &my_charset_latin1);
 	  lex->var_list.push_back(new set_var(lex->option_type,
-					      find_sys_var("client_character_set"),
-					      $3));
+					      find_sys_var("client_collation"),
+					      csname));
 	}
 	| PASSWORD equal text_or_password
 	  {