WL#1622 "SQL Syntax for Prepared Statements": Post-review fixes (1 of 2)

mysql-test/r/ps.result

@@ -21,7 +21,7 @@ a	b
 2	two
 3	three
 deallocate prepare no_such_statement;
-ERROR HY000: Undefined prepared statement
+ERROR HY000: Unknown prepared statement handler (no_such_statement) given to DEALLOCATE PREPARE
 execute stmt1;
 ERROR HY000: Wrong arguments to mysql_execute
 prepare stmt2 from 'prepare nested_stmt from "select 1"';
@@ -98,4 +98,18 @@ set @arg00=NULL ;
 prepare stmt1 from 'select 1 FROM t2 where a=?' ;
 execute stmt1 using @arg00 ;
 1
+prepare stmt1 from @nosuchvar;
+ERROR 42000: You have an error in your SQL syntax.  Check the manual that corresponds to your MySQL server version for the right syntax to use near 'NULL' at line 1
+set @ivar= 1234;
+prepare stmt1 from @ivar;
+ERROR 42000: You have an error in your SQL syntax.  Check the manual that corresponds to your MySQL server version for the right syntax to use near '1234' at line 1
+set @fvar= 123.4567;
+prepare stmt1 from @fvar;
+ERROR 42000: You have an error in your SQL syntax.  Check the manual that corresponds to your MySQL server version for the right syntax to use near '123.4567' at line 1
+set @str1 = 'select ?';
+set @str2 = convert(@str1 using ucs2);
+prepare stmt1 from @str2;
+execute stmt1 using @ivar;
+?
+1234
 drop table t1,t2;

mysql-test/t/ps.test

@@ -98,5 +98,22 @@ set @arg00=NULL ;
 prepare stmt1 from 'select 1 FROM t2 where a=?' ;
 execute stmt1 using @arg00 ;
 
+# prepare using variables:
+--error 1064
+prepare stmt1 from @nosuchvar;
+
+set @ivar= 1234;
+--error 1064
+prepare stmt1 from @ivar;
+
+set @fvar= 123.4567;
+--error 1064
+prepare stmt1 from @fvar;
+
+set @str1 = 'select ?';
+set @str2 = convert(@str1 using ucs2);
+prepare stmt1 from @str2;
+execute stmt1 using @ivar;
+
 drop table t1,t2;
 

mysys/my_error.c

@@ -33,6 +33,12 @@ char NEAR errbuff[NRERRBUFFS][ERRMSGSIZE];
        nr	Errno
        MyFlags	Flags
        ...	variable list
+   NOTE
+    The following subset of printf format is supported:
+    "%[0-9.-]*l?[sdu]", where all length flags are parsed but ignored.
+
+    Additionally "%.*s" is supported and "%.*[ud]" is correctly parsed but 
+    length value is ignored.
 */
 
 int my_error(int nr,myf MyFlags, ...)
@@ -43,7 +49,10 @@ int my_error(int nr,myf MyFlags, ...)
   reg2 char	*endpos;
   char		* par;
   char		ebuff[ERRMSGSIZE+20];
+  int           prec_chars;
+  my_bool       prec_supplied;
   DBUG_ENTER("my_error");
+  LINT_INIT(prec_chars); /* protected by prec_supplied */
 
   va_start(ap,MyFlags);
   DBUG_PRINT("my", ("nr: %d  MyFlags: %d  errno: %d", nr, MyFlags, errno));
@@ -59,7 +68,6 @@ int my_error(int nr,myf MyFlags, ...)
     if (tpos[0] != '%')
     {
       *endpos++= *tpos++;	/* Copy ordinary char */
-      olen++;
       continue;
     }
     if (*++tpos == '%')		/* test if %% */
@@ -68,21 +76,48 @@ int my_error(int nr,myf MyFlags, ...)
     }
     else
     {
-      /* Skipp if max size is used (to be compatible with printf) */
-      while (my_isdigit(&my_charset_latin1, *tpos) || *tpos == '.' || *tpos == '-')
-	tpos++;
-      if (*tpos == 'l')				/* Skipp 'l' argument */
-	tpos++;
+      /* 
+        Skip size/precision flags to be compatible with printf. 
+        The only size/precision flag supported is "%.*s". 
+        "%.*u" and "%.*d" cause 
+      */
+      prec_supplied= 0;
+      if (*tpos== '.')
+      {
+        tpos++;
+        olen--;
+        if (*tpos == '*')
+        {
+          tpos++;
+          olen--;
+          prec_chars= va_arg(ap, int); /* get length parameter */
+          prec_supplied= 1;
+        }
+      }
+       
+      if (!prec_supplied)
+      {
+        while (my_isdigit(&my_charset_latin1, *tpos) || *tpos == '.' || 
+               *tpos == '-')
+	 tpos++;
+        
+        if (*tpos == 'l')				/* Skipp 'l' argument */
+	  tpos++;
+      }
+
       if (*tpos == 's')				/* String parameter */
       {
 	par = va_arg(ap, char *);
 	plen = (uint) strlen(par);
+        if (prec_supplied && prec_chars > 0)
+          plen= min((uint)prec_chars, plen);
 	if (olen + plen < ERRMSGSIZE+2)		/* Replace if possible */
 	{
-	  endpos=strmov(endpos,par);
-	  tpos++;
-	  olen+=plen-2;
-	  continue;
+          memcpy(endpos,par, plen);
+          endpos += plen;
+          tpos++;
+          olen+=plen-2;
+          continue;
 	}
       }
       else if (*tpos == 'd' || *tpos == 'u')	/* Integer parameter */

sql/item.cc

@@ -253,7 +253,7 @@ bool Item::get_time(TIME *ltime)
   return 0;
 }
 
-CHARSET_INFO * Item::default_charset() const
+CHARSET_INFO * Item::default_charset() 
 {
   return current_thd->variables.collation_connection;
 }
@@ -678,11 +678,6 @@ void Item_param::set_value(const char *str, uint length, CHARSET_INFO *ci)
   DBUG_VOID_RETURN;
 }
 
-void Item_param::set_value(const char *str, uint length)
-{
-  set_value(str, length, default_charset());
-}
-
 
 void Item_param::set_time(TIME *tm, timestamp_type type)
 { 

sql/item.h

@@ -220,7 +220,7 @@ public:
   virtual Item *real_item() { return this; }
   virtual Item *get_tmp_table_item(THD *thd) { return copy_or_same(thd); }
 
-  CHARSET_INFO *default_charset() const;
+  static CHARSET_INFO *default_charset();
   virtual CHARSET_INFO *compare_collation() { return NULL; }
 
   virtual bool walk(Item_processor processor, byte *arg)
@@ -413,7 +413,6 @@ public:
   void set_null();
   void set_int(longlong i);
   void set_double(double i);
-  void set_value(const char *str, uint length);
   void set_value(const char *str, uint length, CHARSET_INFO *ci);
   void set_long_str(const char *str, ulong length);
   void set_long_binary(const char *str, ulong length);

sql/mysqld.cc

@@ -4842,9 +4842,12 @@ struct show_var_st status_vars[]= {
   {"Com_unlock_tables",	       (char*) (com_stat+(uint) SQLCOM_UNLOCK_TABLES),SHOW_LONG},
   {"Com_update",	       (char*) (com_stat+(uint) SQLCOM_UPDATE),SHOW_LONG},
   {"Com_update_multi",	       (char*) (com_stat+(uint) SQLCOM_UPDATE_MULTI),SHOW_LONG},
-  {"Com_prepare_sql",          (char*) (com_stat+(uint) SQLCOM_PREPARE), SHOW_LONG}, 
-  {"Com_execute_sql",          (char*) (com_stat+(uint) SQLCOM_EXECUTE), SHOW_LONG},
-  {"Com_dealloc_sql",          (char*) (com_stat+(uint) SQLCOM_DEALLOCATE_PREPARE), SHOW_LONG},
+  {"Com_prepare_sql",          (char*) (com_stat+(uint) SQLCOM_PREPARE),
+   SHOW_LONG}, 
+  {"Com_execute_sql",          (char*) (com_stat+(uint) SQLCOM_EXECUTE), 
+   SHOW_LONG},
+  {"Com_dealloc_sql",          (char*) (com_stat+(uint) 
+                                        SQLCOM_DEALLOCATE_PREPARE), SHOW_LONG},
   {"Connections",              (char*) &thread_id,              SHOW_LONG_CONST},
   {"Created_tmp_disk_tables",  (char*) &created_tmp_disk_tables,SHOW_LONG},
   {"Created_tmp_files",	       (char*) &my_tmp_file_created,	SHOW_LONG},

sql/share/czech/errmsg.txt

@@ -255,7 +255,7 @@ character-set=latin2
 "Key reference and table reference doesn't match",
 "Operand should contain %d column(s)",
 "Subquery returns more than 1 row",
-"Unknown prepared statement handler (%ld) given to %s",
+"Unknown prepared statement handler (%.*s) given to %s",
 "Help database is corrupt or does not exist",
 "Cyclic reference on subqueries",
 "Converting column '%s' from %s to %s",

sql/share/dutch/errmsg.txt

@@ -257,7 +257,7 @@ character-set=latin1
 "Key reference and table reference doesn't match",
 "Operand should contain %d column(s)",
 "Subquery returns more than 1 row",
-"Unknown prepared statement handler (%ld) given to %s",
+"Unknown prepared statement handler (%.*s) given to %s",
 "Help database is corrupt or does not exist",
 "Cyclic reference on subqueries",
 "Converting column '%s' from %s to %s",

sql/share/english/errmsg.txt

@@ -246,7 +246,7 @@ character-set=latin1
 "Key reference and table reference doesn't match",
 "Operand should contain %d column(s)",
 "Subquery returns more than 1 row",
-"Unknown prepared statement handler (%ld) given to %s",
+"Unknown prepared statement handler (%.*s) given to %s",
 "Help database is corrupt or does not exist",
 "Cyclic reference on subqueries",
 "Converting column '%s' from %s to %s",

sql/share/estonian/errmsg.txt

@@ -251,7 +251,7 @@ character-set=latin7
 "Key reference and table reference doesn't match",
 "Operand should contain %d column(s)",
 "Subquery returns more than 1 row",
-"Unknown prepared statement handler (%ld) given to %s",
+"Unknown prepared statement handler (%.*s) given to %s",
 "Help database is corrupt or does not exist",
 "Cyclic reference on subqueries",
 "Converting column '%s' from %s to %s",

sql/share/french/errmsg.txt

@@ -246,7 +246,7 @@ character-set=latin1
 "Key reference and table reference doesn't match",
 "Operand should contain %d column(s)",
 "Subquery returns more than 1 row",
-"Unknown prepared statement handler (%ld) given to %s",
+"Unknown prepared statement handler (%.*s) given to %s",
 "Help database is corrupt or does not exist",
 "Cyclic reference on subqueries",
 "Converting column '%s' from %s to %s",

sql/share/german/errmsg.txt

@@ -258,7 +258,7 @@ character-set=latin1
 "Schlüssel- und Tabellenverweis passen nicht zusammen",
 "Operand solle %d Spalte(n) enthalten",
 "Unterabfrage lieferte mehr als einen Datensatz zurück",
-"Unbekannter Prepared-Statement-Handler (%ld) für %s angegeben",
+"Unbekannter Prepared-Statement-Handler (%.*s) für %s angegeben",
 "Die Hilfe-Datenbank ist beschädigt oder existiert nicht",
 "Zyklischer Verweis in Unterabfragen",
 "Spalte '%s' wird von %s nach %s umgewandelt",

sql/share/greek/errmsg.txt

@@ -246,7 +246,7 @@ character-set=greek
 "Key reference and table reference doesn't match",
 "Operand should contain %d column(s)",
 "Subquery returns more than 1 row",
-"Unknown prepared statement handler (%ld) given to %s",
+"Unknown prepared statement handler (%.*s) given to %s",
 "Help database is corrupt or does not exist",
 "Cyclic reference on subqueries",
 "Converting column '%s' from %s to %s",

sql/share/hungarian/errmsg.txt

@@ -248,7 +248,7 @@ character-set=latin2
 "Key reference and table reference doesn't match",
 "Operand should contain %d column(s)",
 "Subquery returns more than 1 row",
-"Unknown prepared statement handler (%ld) given to %s",
+"Unknown prepared statement handler (%.*s) given to %s",
 "Help database is corrupt or does not exist",
 "Cyclic reference on subqueries",
 "Converting column '%s' from %s to %s",

sql/share/italian/errmsg.txt

@@ -246,7 +246,7 @@ character-set=latin1
 "Key reference and table reference doesn't match",
 "Operand should contain %d column(s)",
 "Subquery returns more than 1 row",
-"Unknown prepared statement handler (%ld) given to %s",
+"Unknown prepared statement handler (%.*s) given to %s",
 "Help database is corrupt or does not exist",
 "Cyclic reference on subqueries",
 "Converting column '%s' from %s to %s",

sql/share/japanese/errmsg.txt

@@ -248,7 +248,7 @@ character-set=ujis
 "Key reference and table reference doesn't match",
 "Operand should contain %d column(s)",
 "Subquery returns more than 1 row",
-"Unknown prepared statement handler (%ld) given to %s",
+"Unknown prepared statement handler (%.*s) given to %s",
 "Help database is corrupt or does not exist",
 "Cyclic reference on subqueries",
 "Converting column '%s' from %s to %s",

sql/share/korean/errmsg.txt

@@ -246,7 +246,7 @@ character-set=euckr
 "Key reference and table reference doesn't match",
 "Operand should contain %d column(s)",
 "Subquery returns more than 1 row",
-"Unknown prepared statement handler (%ld) given to %s",
+"Unknown prepared statement handler (%.*s) given to %s",
 "Help database is corrupt or does not exist",
 "Cyclic reference on subqueries",
 "Converting column '%s' from %s to %s",

sql/share/norwegian-ny/errmsg.txt

@@ -248,7 +248,7 @@ character-set=latin1
 "Key reference and table reference doesn't match",
 "Operand should contain %d column(s)",
 "Subquery returns more than 1 row",
-"Unknown prepared statement handler (%ld) given to %s",
+"Unknown prepared statement handler (%.*s) given to %s",
 "Help database is corrupt or does not exist",
 "Cyclic reference on subqueries",
 "Converting column '%s' from %s to %s",

sql/share/norwegian/errmsg.txt

@@ -248,7 +248,7 @@ character-set=latin1
 "Key reference and table reference doesn't match",
 "Operand should contain %d column(s)",
 "Subquery returns more than 1 row",
-"Unknown prepared statement handler (%ld) given to %s",
+"Unknown prepared statement handler (%.*s) given to %s",
 "Help database is corrupt or does not exist",
 "Cyclic reference on subqueries",
 "Converting column '%s' from %s to %s",

sql/share/polish/errmsg.txt

@@ -250,7 +250,7 @@ character-set=latin2
 "Key reference and table reference doesn't match",
 "Operand should contain %d column(s)",
 "Subquery returns more than 1 row",
-"Unknown prepared statement handler (%ld) given to %s",
+"Unknown prepared statement handler (%.*s) given to %s",
 "Help database is corrupt or does not exist",
 "Cyclic reference on subqueries",
 "Converting column '%s' from %s to %s",

sql/share/portuguese/errmsg.txt

@@ -247,7 +247,7 @@ character-set=latin1
 "Referência da chave e referência da tabela não coincidem",
 "Operand should contain %d column(s)",
 "Subconsulta retorna mais que 1 registro",
-"Desconhecido manipulador de declaração preparado (%ld) determinado para %s",
+"Desconhecido manipulador de declaração preparado (%.*s) determinado para %s",
 "Banco de dado de ajuda corrupto ou não existente",
 "Referência cíclica em subconsultas",
 "Convertendo coluna '%s' de %s para %s",

sql/share/romanian/errmsg.txt

@@ -250,7 +250,7 @@ character-set=latin2
 "Key reference and table reference doesn't match",
 "Operand should contain %d column(s)",
 "Subquery returns more than 1 row",
-"Unknown prepared statement handler (%ld) given to %s",
+"Unknown prepared statement handler (%.*s) given to %s",
 "Help database is corrupt or does not exist",
 "Cyclic reference on subqueries",
 "Converting column '%s' from %s to %s",

sql/share/russian/errmsg.txt

@@ -248,7 +248,7 @@ character-set=koi8r
 "Key reference and table reference doesn't match",
 "   %d ",
 "    ",
-"Unknown prepared statement handler (%ld) given to %s",
+"Unknown prepared statement handler (%.*s) given to %s",
 "Help database is corrupt or does not exist",
 "   ",
 "  '%s'  %s  %s",

sql/share/slovak/errmsg.txt

@@ -254,7 +254,7 @@ character-set=latin2
 "Key reference and table reference doesn't match",
 "Operand should contain %d column(s)",
 "Subquery returns more than 1 row",
-"Unknown prepared statement handler (%ld) given to %s",
+"Unknown prepared statement handler (%.*s) given to %s",
 "Help database is corrupt or does not exist",
 "Cyclic reference on subqueries",
 "Converting column '%s' from %s to %s",

sql/share/spanish/errmsg.txt

@@ -248,7 +248,7 @@ character-set=latin1
 "Referencia de llave y referencia de tabla no coinciden",
 "Operando debe tener %d columna(s)",
 "Subconsulta retorna mas que 1 línea",
-"Desconocido preparado comando handler (%ld) dado para %s",
+"Desconocido preparado comando handler (%.*s) dado para %s",
 "Base de datos Help está corrupto o no existe",
 "Cíclica referencia en subconsultas",
 "Convirtiendo columna '%s' de %s para %s",

sql/share/swedish/errmsg.txt

@@ -246,7 +246,7 @@ character-set=latin1
 "Nyckelreferensen och tabellreferensen stämmer inte överens",
 "Operand should contain %d column(s)",
 "Subquery returnerade mer än 1 rad",
-"Okänd PREPARED STATEMENT id (%ld) var given till %s",
+"Okänd PREPARED STATEMENT id (%.*s) var given till %s",
 "Hjälpdatabasen finns inte eller är skadad",
 "Cyklisk referens i subqueries",
 "Konvertar kolumn '%s' från %s till %s",

sql/share/ukrainian/errmsg.txt

@@ -251,7 +251,7 @@ character-set=koi8u
 "Key reference and table reference doesn't match",
 "    %d æ",
 "  ¦ i 1 ",
-"Unknown prepared statement handler (%ld) given to %s",
+"Unknown prepared statement handler (%.*s) given to %s",
 "Help database is corrupt or does not exist",
 "̦   Ц",
 "  '%s'  %s  %s",

sql/sql_class.h

@@ -556,8 +556,13 @@ public:
   Statement *find(ulong id)
   {
     if (last_found_statement == 0 || id != last_found_statement->id)
-      last_found_statement= (Statement *) hash_search(&st_hash, (byte *) &id,
-                                                      sizeof(id));
+    {
+      Statement *stmt;
+      stmt= (Statement *) hash_search(&st_hash, (byte *) &id, sizeof(id));
+      if (stmt->name.str)
+        return NULL;
+      last_found_statement= stmt;
+    }
     return last_found_statement;
   }
   void erase(Statement *statement)

sql/sql_lex.h

@@ -608,7 +608,13 @@ typedef struct st_lex
   bool safe_to_cache_query;
   /* Prepared statements SQL syntax:*/
   LEX_STRING prepared_stmt_name; /* Statement name (in all queries) */
-  LEX_STRING prepared_stmt_code; /* Statement query (in PREPARE )*/
+  /* 
+    Prepared statement query text or name of variable that holds the
+    prepared statement (in PREPARE ... queries)
+  */
+  LEX_STRING prepared_stmt_code; 
+  /* If true, prepared_stmt_code is a name of variable that holds the query */
+  bool prepared_stmt_code_is_varref;
   /* Names of user variables holding parameters (in EXECUTE) */
   List<LEX_STRING> prepared_stmt_params; 
   st_lex() {}

sql/sql_parse.cc

@@ -1972,14 +1972,90 @@ mysql_execute_command(THD *thd)
   }
   case SQLCOM_PREPARE:
   {   
-    DBUG_PRINT("info", ("PREPARE: %.*s FROM '%.*s' \n", 
-                        lex->prepared_stmt_name.length,
-                        lex->prepared_stmt_name.str,
-                        lex->prepared_stmt_code.length,
-                        lex->prepared_stmt_code.str));
+    char *query_str;
+    uint query_len;
+    if (lex->prepared_stmt_code_is_varref)
+    {
+      /* This is PREPARE stmt FROM @var*/
+      String str;
+      CHARSET_INFO *to_cs= thd->variables.collation_connection;
+      CHARSET_INFO *from_cs;
+      const char *buf;
+      uint  buf_len;
+      bool need_conversion;
+      //// psergey: find the variable and convert it.
+      LINT_INIT(from_cs);
+      user_var_entry *entry;
+      uint32 unused;
+      if ((entry= 
+             (user_var_entry*)hash_search(&thd->user_vars, 
+                                          (byte*)lex->prepared_stmt_code.str,
+                                          lex->prepared_stmt_code.length))
+          && entry->value)
+      {
+        switch (entry->type)
+        {
+          case REAL_RESULT:
+            str.set(*(double*)entry->value, NOT_FIXED_DEC, to_cs);
+            buf_len= str.length();
+            buf= str.ptr();
+            need_conversion= false;
+            break;
+          case INT_RESULT:
+            str.set(*(longlong*)entry->value, to_cs);
+            buf_len= str.length();
+            buf= str.ptr();
+            need_conversion= false;
+            break;
+          case STRING_RESULT:
+            buf_len= entry->length;
+            buf= entry->value;
+            from_cs = entry->collation.collation;
+            need_conversion= String::needs_conversion(entry->length, from_cs,
+                                                      to_cs, &unused);
+            break;
+          default:
+            buf= "";
+            need_conversion= false;
+            buf_len= 0;
+            DBUG_ASSERT(0);
+        }
+      }
+      else
+      {
+        from_cs= &my_charset_bin;
+        str.set("NULL", 4, from_cs);
+        buf= str.ptr();
+        buf_len= str.length();
+        need_conversion= String::needs_conversion(str.length(), from_cs,
+                                                  to_cs, &unused);
+      }
+       
+      query_len = need_conversion? (buf_len* to_cs->mbmaxlen) : buf_len;
+      if (!(query_str= alloc_root(&thd->mem_root, query_len+1)))
+      {
+        send_error(thd, ER_OUT_OF_RESOURCES);
+      }              
+      
+      if (need_conversion)
+        query_len= copy_and_convert(query_str, query_len, to_cs, buf, buf_len,
+                                    from_cs);
+      else
+        memcpy(query_str, buf, query_len);
+      query_str[query_len] = 0;
+    }
+    else
+    {
+      DBUG_PRINT("info", ("PREPARE: %.*s FROM '%.*s' \n", 
+                          lex->prepared_stmt_name.length,
+                          lex->prepared_stmt_name.str,
+                          lex->prepared_stmt_code.length,
+                          lex->prepared_stmt_code.str));
+      query_str= lex->prepared_stmt_code.str;
+      query_len= lex->prepared_stmt_code.length + 1;
+    }
     thd->command= COM_PREPARE;
-    if (!mysql_stmt_prepare(thd, lex->prepared_stmt_code.str,
-                            lex->prepared_stmt_code.length + 1, 
+    if (!mysql_stmt_prepare(thd, query_str, query_len + 1, 
                             &lex->prepared_stmt_name))    
       send_ok(thd, 0L, 0L, "Statement prepared");
     break;
@@ -2005,7 +2081,12 @@ mysql_execute_command(THD *thd)
       send_ok(thd);
     }
     else
-      send_error(thd,ER_UNKNOWN_STMT_HANDLER,"Undefined prepared statement");
+    {
+      res= -1;
+      my_error(ER_UNKNOWN_STMT_HANDLER, MYF(0),
+               lex->prepared_stmt_name.length, lex->prepared_stmt_name.str,
+               "DEALLOCATE PREPARE");
+    }
     break;
   }
   case SQLCOM_DO:
@@ -3438,7 +3519,7 @@ error:
 */
 
 int check_one_table_access(THD *thd, ulong privilege, TABLE_LIST *tables)
-					 
+
 {
   if (check_access(thd, privilege, tables->db, &tables->grant.privilege,0,0))
     return 1;

sql/sql_prepare.cc

@@ -135,7 +135,8 @@ find_prepared_statement(THD *thd, ulong id, const char *where,
 
   if (stmt == 0 || stmt->type() != Statement::PREPARED_STATEMENT)
   {
-    my_error(ER_UNKNOWN_STMT_HANDLER, MYF(0), id, where);
+    char llbuf[22];
+    my_error(ER_UNKNOWN_STMT_HANDLER, MYF(0), 22, llstr(id, llbuf), where);
     if (se == SEND_ERROR)
       send_error(thd);
     return 0;
@@ -392,7 +393,7 @@ void set_param_date(Item_param *param, uchar **pos, ulong len)
 void set_param_str(Item_param *param, uchar **pos, ulong len)
 {
   ulong length= get_param_length(pos, len);
-  param->set_value((const char *)*pos, length);
+  param->set_value((const char *)*pos, length, Item::default_charset());
   *pos+= length;
 }
 
@@ -1376,7 +1377,7 @@ static int send_prepare_results(Prepared_statement *stmt, bool text_protocol)
     goto error;
   }
   if (res == 0)
-    DBUG_RETURN(text_protocol?0:send_prep_stmt(stmt, 0));
+    DBUG_RETURN(text_protocol? 0 : send_prep_stmt(stmt, 0));
 error:
   if (res < 0)
     send_error(thd, thd->killed ? ER_SERVER_SHUTDOWN : 0);
@@ -1417,25 +1418,31 @@ static bool init_param_array(Prepared_statement *stmt)
 
 
 /*
+  Given a query string with parameter markers, create a Prepared Statement
+  from it and send PS info back to the client.
+  
   SYNOPSIS
     mysql_stmt_prepare()
-      packet         Prepared query 
-      packet_length  query length, with ignored trailing NULL or quote char.
+      packet         query to be prepared 
+      packet_length  query string length, including ignored trailing NULL or 
+                     quote char.
       name           NULL or statement name. For unnamed statements binary PS
-                     protocol is used, for named statmenents text protocol is 
+                     protocol is used, for named statements text protocol is 
                      used.
-
-  Parse the query and send the total number of parameters 
-  and resultset metadata information back to client (if any), 
-  without executing the query i.e. without any log/disk 
-  writes. This will allow the queries to be re-executed 
-  without re-parsing during execute. 
-
-  If parameter markers are found in the query, then store 
-  the information using Item_param along with maintaining a
-  list in lex->param_array, so that a fast and direct
-  retrieval can be made without going through all field
-  items.
+  RETURN 
+    0      OK, statement prepared successfully
+    other  Error
+  
+  NOTES
+    This function parses the query and sends the total number of parameters 
+    and resultset metadata information back to client (if any), without 
+    executing the query i.e. without any log/disk writes. This allows the 
+    queries to be re-executed without re-parsing during execute. 
+
+    If parameter markers are found in the query, then store the information
+    using Item_param along with maintaining a list in lex->param_array, so 
+    that a fast and direct retrieval can be made without going through all 
+    field items.
    
 */
 
@@ -1672,13 +1679,14 @@ set_params_data_err:
 void mysql_sql_stmt_execute(THD *thd, LEX_STRING *stmt_name)
 {
   Prepared_statement *stmt;
-  DBUG_ENTER("mysql_stmt_execute");
+  DBUG_ENTER("mysql_sql_stmt_execute");
     
   if (!(stmt= (Prepared_statement*)thd->stmt_map.find_by_name(stmt_name)))
   {
-      send_error(thd, ER_UNKNOWN_STMT_HANDLER, 
-                 "Undefined prepared statement");
-      DBUG_VOID_RETURN;
+    my_error(ER_UNKNOWN_STMT_HANDLER, MYF(0), stmt_name->length,
+             stmt_name->str, "EXECUTE");
+    send_error(thd);
+    DBUG_VOID_RETURN;
   }
 
   if (stmt->param_count != thd->lex->prepared_stmt_params.elements)

sql/sql_yacc.yy

@@ -726,7 +726,7 @@ bool my_yyoverflow(short **a, YYSTYPE **b,int *yystacksize);
 	precision subselect_start opt_and charset
 	subselect_end select_var_list select_var_list_init help opt_len
 	opt_extended_describe
-        prepare execute deallocate 
+        prepare prepare_src execute deallocate 
 END_OF_INPUT
 
 %type <NONE>
@@ -816,7 +816,7 @@ deallocate:
         };
 
 prepare:
-        PREPARE_SYM ident FROM TEXT_STRING_sys
+        PREPARE_SYM ident FROM prepare_src
         {
           THD *thd=YYTHD;
           LEX *lex= thd->lex;
@@ -827,9 +827,24 @@ prepare:
           }
           lex->sql_command= SQLCOM_PREPARE;
           lex->prepared_stmt_name= $2;
-          lex->prepared_stmt_code= $4;
         };
 
+prepare_src:
+        TEXT_STRING_sys
+        {
+          THD *thd=YYTHD;
+          LEX *lex= thd->lex;
+          lex->prepared_stmt_code= $1;
+          lex->prepared_stmt_code_is_varref= false;
+        }
+        | '@' ident_or_text
+        {
+          THD *thd=YYTHD;
+          LEX *lex= thd->lex;
+          lex->prepared_stmt_code= $2;
+          lex->prepared_stmt_code_is_varref= true;
+        };
+        
 execute:
         EXECUTE_SYM ident
         {