fixed & added comments (according to Igor's review and a bit more)

13 files changed, 150 insertions, 107 deletions

diff --git a/sql/item_strfunc.h b/sql/item_strfunc.h
index c4881a465a2..111f0e20698 100644
--- a/sql/item_strfunc.h
+++ b/sql/item_strfunc.h
@@ -261,7 +261,7 @@ public:
   Returns strcat('*', octet2hex(sha1(sha1(password)))). '*' stands for new
   password format, sha1(sha1(password) is so-called hash_stage2 value.
   Length of returned string is always 41 byte. To find out how entire
-  authentification procedure works, see comments in password.c.
+  authentication procedure works, see comments in password.c.
 */
 
 class Item_func_password :public Item_str_func
diff --git a/sql/parse_file.cc b/sql/parse_file.cc
index d10d395d6e5..16674793b48 100644
--- a/sql/parse_file.cc
+++ b/sql/parse_file.cc
@@ -57,11 +57,11 @@ write_escaped_string(IO_CACHE *file, LEX_STRING *val_s)
       if (my_b_append(file, (const byte *)"\\n", 2))
 	return TRUE;
       break;
-    case '\0': // problem for some string processing utilites
+    case '\0': // problem for some string processing utilities
       if (my_b_append(file, (const byte *)"\\0", 2))
 	return TRUE;
       break;
-    case 26: // problem for windows utilites (Ctrl-Z)
+    case 26: // problem for windows utilities (Ctrl-Z)
       if (my_b_append(file, (const byte *)"\\z", 2))
 	return TRUE;
       break;
@@ -253,7 +253,7 @@ sql_create_definition_file(const LEX_STRING *dir, const LEX_STRING *file_name,
   {
     if (old_version != ULONGLONG_MAX && max_versions != 0)
     {
-      // save buckup
+      // save backup
       char path_arc[FN_REFLEN];
       // backup old version
       char path_to[FN_REFLEN];
@@ -383,9 +383,9 @@ sql_parse_prepare(const LEX_STRING *file_name, MEM_ROOT *mem_root,
   }
 
   end= parser->end= parser->buff + len;
-  *end= '\0'; // barriaer for more simple parsing
+  *end= '\0'; // barrier for more simple parsing
 
-  // 7 = 5 (TYPE=) + 1 (leter at least of type name) + 1 ('\n')
+  // 7 = 5 (TYPE=) + 1 (letter at least of type name) + 1 ('\n')
   if (len < 7 ||
       parser->buff[0] != 'T' ||
       parser->buff[1] != 'Y' ||
diff --git a/sql/parse_file.h b/sql/parse_file.h
index cf34a5095a4..82a89dffd18 100644
--- a/sql/parse_file.h
+++ b/sql/parse_file.h
@@ -23,7 +23,7 @@
 enum file_opt_type {
   FILE_OPTIONS_STRING,		/* String (LEX_STRING) */
   FILE_OPTIONS_ESTRING,		/* Escaped string (LEX_STRING) */
-  FILE_OPTIONS_ULONGLONG,	/* ulonglong parapeter (ulonglong) */
+  FILE_OPTIONS_ULONGLONG,	/* ulonglong parameter (ulonglong) */
   FILE_OPTIONS_REV,		/* Revision version number (ulonglong) */
   FILE_OPTIONS_TIMESTAMP,	/* timestamp (LEX_STRING have to be
 				   allocated with length 20 (19+1) */
diff --git a/sql/password.c b/sql/password.c
index 0ac91346a55..115c1ef83ef 100644
--- a/sql/password.c
+++ b/sql/password.c
@@ -65,7 +65,7 @@
 #include <sha1.h>
 #include "mysql.h"
 
-/************ MySQL 3.23-4.0 authentification routines: untouched ***********/
+/************ MySQL 3.23-4.0 authentication routines: untouched ***********/
 
 /*
   New (MySQL 3.21+) random generation structure initialization
@@ -280,7 +280,7 @@ void make_password_from_salt_323(char *to, const ulong *salt)
 
 
 /*
-     **************** MySQL 4.1.1 authentification routines *************
+     **************** MySQL 4.1.1 authentication routines *************
 */
 
 /*
diff --git a/sql/sql_acl.cc b/sql/sql_acl.cc
index b4d2e9e1c76..4a970b6f018 100644
--- a/sql/sql_acl.cc
+++ b/sql/sql_acl.cc
@@ -17,8 +17,8 @@
 
 /*
   The privileges are saved in the following tables:
-  mysql/user	 ; super user who are allowed to do almoust anything
-  mysql/host	 ; host priviliges. This is used if host is empty in mysql/db.
+  mysql/user	 ; super user who are allowed to do almost anything
+  mysql/host	 ; host privileges. This is used if host is empty in mysql/db.
   mysql/db	 ; database privileges / user
 
   data in tables is sorted according to how many not-wild-cards there is
@@ -597,7 +597,7 @@ static int acl_compare(ACL_ACCESS *a,ACL_ACCESS *b)
                 thd->host, thd->ip, thd->user are used for checks.
     mqh         user resources; on success mqh is reset, else
                 unchanged
-    passwd      scrambled & crypted password, recieved from client
+    passwd      scrambled & crypted password, received from client
                 (to check): thd->scramble or thd->scramble_323 is
                 used to decrypt passwd, so they must contain
                 original random string,
@@ -608,7 +608,7 @@ static int acl_compare(ACL_ACCESS *a,ACL_ACCESS *b)
   RETURN VALUE
     0  success: thd->priv_user, thd->priv_host, thd->master_access, mqh are
        updated
-    1  user not found or authentification failure
+    1  user not found or authentication failure
     2  user found, has long (4.1.1) salt, but passwd is in old (3.23) format.
    -1  user found, has short (3.23) salt, but passwd is in new (4.1.1) format.
 */
@@ -748,7 +748,7 @@ int acl_getroot(THD *thd, USER_RESOURCES  *mqh,
 	break;
       }
       DBUG_PRINT("info",("checkpoint 2"));
-      /* If X509 issuer is speified, we check it... */
+      /* If X509 issuer is specified, we check it... */
       if (acl_user->x509_issuer)
       {
         DBUG_PRINT("info",("checkpoint 3"));
@@ -810,7 +810,7 @@ int acl_getroot(THD *thd, USER_RESOURCES  *mqh,
 /*
  * This is like acl_getroot() above, but it doesn't check password,
  * and we don't care about the user resources.
- * Used to get access rights for SQL SECURITY DEFINER invokation of
+ * Used to get access rights for SQL SECURITY DEFINER invocation of
  * stored procedures.
  */
 int acl_getroot_no_password(THD *thd)
@@ -1831,7 +1831,7 @@ GRANT_TABLE::GRANT_TABLE(const char *h, const char *d,const char *u,
 {
   /* Host given by user */
   orig_host=  strdup_root(&memex,h);
-  /* Convert empty hostname to '%' for easy comparision */
+  /* Convert empty hostname to '%' for easy comparison */
   host=  orig_host[0] ? orig_host : (char*) "%";
   db =   strdup_root(&memex,d);
   user = strdup_root(&memex,u);
@@ -2778,7 +2778,7 @@ void grant_reload(THD *thd)
 /****************************************************************************
   Check table level grants
 
-  SYNPOSIS
+  SYNOPSIS
    bool check_grant()
    thd		Thread handler
    want_access  Bits of privileges user needs to have
@@ -2792,7 +2792,7 @@ void grant_reload(THD *thd)
 
    RETURN
      0  ok
-     1  Error: User did not have the requested privielges
+     1  Error: User did not have the requested privileges
 ****************************************************************************/
 
 bool check_grant(THD *thd, ulong want_access, TABLE_LIST *tables,
@@ -3870,8 +3870,8 @@ int wild_case_compare(CHARSET_INFO *cs, const char *str,const char *wildstr)
   fill effective privileges for table
 
   SYNOPSIS
-    get_effectlige_privileges()
-    thd     thread handleg
+    fill_effective_table_privileges()
+    thd     thread handler
     grant   grants table descriptor
     db      db name
     table   table name
diff --git a/sql/sql_lex.cc b/sql/sql_lex.cc
index f5382e6df99..586075b2f69 100644
--- a/sql/sql_lex.cc
+++ b/sql/sql_lex.cc
@@ -1537,11 +1537,17 @@ void st_select_lex::print_limit(THD *thd, String *str)
 
 
 /*
-  Check is merging algorithm can be used on this VIEW
+  Check whether the merging algorithm can be used on this VIEW
 
   SYNOPSIS
     st_lex::can_be_merged()
 
+  DESCRIPTION
+    We can apply merge algorithm if it is single SELECT view (we do not
+    count SELECTs of underlying views) and we have not grpouping, ordering,
+    HAVING clause, aggregate functions, DISTINCT clause, LIMIT clause and
+    several underlying tables.
+
   RETURN
     FALSE - only temporary table algorithm can be used
     TRUE  - merge algorithm can be used
@@ -1569,12 +1575,18 @@ bool st_lex::can_be_merged()
           select_lex.select_limit == HA_POS_ERROR);
 }
 
+
 /*
   check if command can use VIEW with MERGE algorithm (for top VIEWs)
 
   SYNOPSIS
     st_lex::can_use_merged()
 
+  DESCRIPTION
+    Only listed here commands can use merge algorithm in top level
+    SELECT_LEX (for subqueries will be used merge algorithm if
+    st_lex::can_not_use_merged() is not TRUE).
+
   RETURN
     FALSE - command can't use merged VIEWs
     TRUE  - VIEWs with MERGE algorithms can be used
@@ -1601,11 +1613,15 @@ bool st_lex::can_use_merged()
 }
 
 /*
-  check if command can't use merged views in any part of command
+  Check if command can't use merged views in any part of command
 
   SYNOPSIS
     st_lex::can_not_use_merged()
 
+  DESCRIPTION
+    Temporary table algorithm will be used on all SELECT levels for queries
+    listed here (see also st_lex::can_use_merged()).
+
   RETURN
     FALSE - command can't use merged VIEWs
     TRUE  - VIEWs with MERGE algorithms can be used
@@ -1673,16 +1689,16 @@ void st_select_lex_unit::set_limit(SELECT_LEX *values,
 
 
 /*
-  Unlink first table from global table list and first table from outer select
-  list (lex->select_lex)
+  Unlink the first table from the global table list and the first table from
+  outer select (lex->select_lex) local list
 
   SYNOPSIS
     unlink_first_table()
-    link_to_local	Set to 1 if caller should link this table to local
+    link_to_local	Set to 1 if caller should link this table to local list
 
   NOTES
-    We rely on fact that first table in both list are same or local list
-    is empty
+    We assume that first tables in both lists is the same table or the local
+    list is empty.
 
   RETURN
     0	If 'query_tables' == 0
@@ -1711,8 +1727,8 @@ TABLE_LIST *st_lex::unlink_first_table(bool *link_to_local)
       select_lex.table_list.elements--;	//safety
       first->next_local= 0;
       /*
-	reorder global list to keep first tables the same in both lists
-	(if it is need)
+        Ensure that the global list has the same first table as the local
+        list.
       */
       first_lists_tables_same();
     }
@@ -1729,11 +1745,12 @@ TABLE_LIST *st_lex::unlink_first_table(bool *link_to_local)
      st_lex::first_lists_tables_same()
 
   NOTES
-    In many cases first table of main SELECT_LEX have special meaning =>
-    check that it is first table in global list and relink it first in
-    queries_tables list if it is necessary (we need such relinking only
-    for queries with subqueries in select list, in this case tables of
-    subqueries will go to global list first)
+    In many cases (for example, usual INSERT/DELETE/...) the first table of
+    main SELECT_LEX have special meaning => check that it is the first table
+    in global list and re-link to be first in the global list if it is
+    necessary.  We need such re-linking only for queries with sub-queries in
+    the select list, as only in this case tables of sub-queries will go to
+    the global list first.
 */
 
 void st_lex::first_lists_tables_same()
@@ -1744,14 +1761,15 @@ void st_lex::first_lists_tables_same()
     TABLE_LIST *next;
     if (query_tables_last == &first_table->next_global)
       query_tables_last= first_table->prev_global;
-    
+
     if ((next= *first_table->prev_global= first_table->next_global))
       next->prev_global= first_table->prev_global;
     /* include in new place */
     first_table->next_global= query_tables;
     /*
-       we are sure that above is not 0, because first_table was not
-       first table in global list => we can do following without check
+       We are sure that query_tables is not 0, because first_table was not
+       first table in the global list => we can use
+       query_tables->prev_global without check of query_tables
     */
     query_tables->prev_global= &first_table->next_global;
     first_table->prev_global= &query_tables;
diff --git a/sql/sql_parse.cc b/sql/sql_parse.cc
index 924e82416ef..59b45400c2a 100644
--- a/sql/sql_parse.cc
+++ b/sql/sql_parse.cc
@@ -108,7 +108,7 @@ static void unlock_locked_tables(THD *thd)
   if (thd->locked_tables)
   {
     thd->lock=thd->locked_tables;
-    thd->locked_tables=0;			// Will be automaticly closed
+    thd->locked_tables=0;			// Will be automatically closed
     close_thread_tables(thd);			// Free tables
   }
 }
@@ -205,13 +205,13 @@ end:
     command      originator of the check: now check_user is called
                  during connect and change user procedures; used for 
                  logging.
-    passwd       scrambled password recieved from client
+    passwd       scrambled password received from client
     passwd_len   length of scrambled password
     db           database name to connect to, may be NULL
     check_count  dont know exactly
 
     Note, that host, user and passwd may point to communication buffer.
-    Current implementation does not depened on that, but future changes
+    Current implementation does not depend on that, but future changes
     should be done with this in mind; 'thd' is INOUT, all other params
     are 'IN'.
 
@@ -269,7 +269,7 @@ int check_user(THD *thd, enum enum_server_command command,
 
   /*
     Clear thd->db as it points to something, that will be freed when 
-    connection is closed. We don't want to accidently free a wrong pointer
+    connection is closed. We don't want to accidentally free a wrong pointer
     if connect failed. Also in case of 'CHANGE USER' failure, current
     database will be switched to 'no database selected'.
   */
@@ -311,7 +311,7 @@ int check_user(THD *thd, enum enum_server_command command,
   /* here res is always >= 0 */
   if (res == 0)
   {
-    if (!(thd->master_access & NO_ACCESS)) // authentification is OK 
+    if (!(thd->master_access & NO_ACCESS)) // authentication is OK 
     {
       DBUG_PRINT("info",
                  ("Capabilities: %d  packet_length: %ld  Host: '%s'  "
@@ -731,7 +731,7 @@ static int check_connection(THD *thd)
 #endif /* HAVE_COMPRESS */
 #ifdef HAVE_OPENSSL
     if (ssl_acceptor_fd)
-      client_flags |= CLIENT_SSL;       /* Wow, SSL is avalaible! */
+      client_flags |= CLIENT_SSL;       /* Wow, SSL is available! */
 #endif /* HAVE_OPENSSL */
 
     end= strnmov(buff, server_version, SERVER_VERSION_LENGTH) + 1;
@@ -1393,7 +1393,7 @@ bool dispatch_command(enum enum_server_command command, THD *thd,
       *passwd++ : strlen(passwd);
     db+= passwd_len + 1;
 #ifndef EMBEDDED_LIBRARY
-    /* Small check for incomming packet */
+    /* Small check for incoming packet */
     if ((uint) ((uchar*) db - net->read_pos) > packet_length)
     {
       send_error(thd, ER_UNKNOWN_COM_ERROR);
@@ -1428,7 +1428,7 @@ bool dispatch_command(enum enum_server_command command, THD *thd,
 
     if (res)
     {
-      /* authentification failure, we shall restore old user */
+      /* authentication failure, we shall restore old user */
       if (res > 0)
         send_error(thd, ER_UNKNOWN_COM_ERROR);
       x_free(thd->user);
@@ -2397,7 +2397,7 @@ mysql_execute_command(THD *thd)
     }
 #endif
     /*
-      If we are using SET CHARSET without DEFAULT, add an implicite
+      If we are using SET CHARSET without DEFAULT, add an implicit
       DEFAULT to not confuse old users. (This may change).
     */
     if ((lex->create_info.used_fields & 
@@ -3537,7 +3537,7 @@ purposes internal to the MySQL server", MYF(0));
     if (thd->locked_tables)
     {
       thd->lock=thd->locked_tables;
-      thd->locked_tables=0;			// Will be automaticly closed
+      thd->locked_tables=0;			// Will be automatically closed
       close_thread_tables(thd);			// Free tables
     }
     if (end_active_trans(thd))
@@ -3984,7 +3984,7 @@ error:
   SYNOPSIS
     check_one_table_access()
     thd			Thread handler
-    privilege		requested privelage
+    privilege		requested privilege
     all_tables		global table list of query
 
   RETURN
@@ -4126,7 +4126,7 @@ check_access(THD *thd, ulong want_access, const char *db, ulong *save_priv,
     want_access		Use should have any of these global rights
 
   WARNING
-    One gets access rigth if one has ANY of the rights in want_access
+    One gets access right if one has ANY of the rights in want_access
     This is useful as one in most cases only need one global right,
     but in some case we want to check if the user has SUPER or
     REPL_CLIENT_ACL rights.
@@ -4888,7 +4888,7 @@ bool add_field_to_list(THD *thd, char *field_name, enum_field_types type,
       /* 
         We are setting TIMESTAMP_OLD_FIELD here only temporary, we will 
         replace this value by TIMESTAMP_DNUN_FIELD or NONE later when 
-        information about all TIMESTAMP fields in table will be availiable.
+        information about all TIMESTAMP fields in table will be available.
       */
       new_field->unireg_check= on_update_value?Field::TIMESTAMP_UN_FIELD:
                                                Field::TIMESTAMP_OLD_FIELD;
@@ -5315,7 +5315,7 @@ TABLE_LIST *st_select_lex::nest_last_join(THD *thd)
 
 
 /*
-  Save names for a join with using clase
+  Save names for a join with using clause
 
   SYNOPSIS
     save_names_for_using_list
@@ -6168,7 +6168,7 @@ int create_table_precheck(THD *thd, TABLE_LIST *tables,
 
   SYNOPSIS
     negate_expression()
-    thd  therad handler
+    thd  thread handler
     expr expression for negation
 
   RETURN
diff --git a/sql/sql_show.cc b/sql/sql_show.cc
index 951fc9de6d4..c80f7cc8a8a 100644
--- a/sql/sql_show.cc
+++ b/sql/sql_show.cc
@@ -762,7 +762,7 @@ mysqld_show_fields(THD *thd, TABLE_LIST *table_list,const char *wild,
 	  protocol->store(field->has_charset() ? field->charset()->name : "NULL",
 			system_charset_info);
         /*
-          Altough TIMESTAMP fields can't contain NULL as its value they
+          Although TIMESTAMP fields can't contain NULL as its value they
           will accept NULL if you will try to insert such value and will
           convert it to current TIMESTAMP. So YES here means that NULL 
           is allowed for assignment but can't be returned.
@@ -781,7 +781,7 @@ mysqld_show_fields(THD *thd, TABLE_LIST *table_list,const char *wild,
         {
           /*
             We have NOW() as default value but we use CURRENT_TIMESTAMP form
-            because it is more SQL standard comatible
+            because it is more SQL standard compatible
           */
           protocol->store("CURRENT_TIMESTAMP", system_charset_info);
         }
@@ -1213,7 +1213,7 @@ mysqld_dump_create_info(THD *thd, TABLE *table, int fd)
 
 /*
   Go through all character combinations and ensure that sql_lex.cc can
-  parse it as an identifer.
+  parse it as an identifier.
 
   SYNOPSIS
   require_quotes()
diff --git a/sql/sql_update.cc b/sql/sql_update.cc
index 39701774b0e..7a643933c46 100644
--- a/sql/sql_update.cc
+++ b/sql/sql_update.cc
@@ -72,7 +72,7 @@ static bool check_fields(THD *thd, List<Item> &items)
   {
     if (!(field= item->filed_for_view_update()))
     {
-      /* as far as item comes from VIEW select list it has name */
+      /* item has name, because it comes from VIEW SELECT list */
       my_error(ER_NONUPDATEABLE_COLUMN, MYF(0), item->name);
       return TRUE;
     }
@@ -589,8 +589,9 @@ int mysql_multi_update_prepare(THD *thd)
   }
 
   /*
-    setup_tables() need for VIEWs. JOIN::prepare() will not do it second
-    time.
+    setup_tables() need for VIEWs. JOIN::prepare() will call setup_tables()
+    second time, but this call will do nothing (there are check for second
+    call in setup_tables()).
   */
   if (setup_tables(thd, table_list, &lex->select_lex.where) ||
       (thd->lex->select_lex.no_wrap_view_item= 1,
diff --git a/sql/sql_view.cc b/sql/sql_view.cc
index 50c260fb642..e9728d12734 100644
--- a/sql/sql_view.cc
+++ b/sql/sql_view.cc
@@ -80,6 +80,18 @@ int mysql_create_view(THD *thd,
   }
 
 #ifndef NO_EMBEDDED_ACCESS_CHECKS
+  /*
+    Privilege check for view creation:
+    - user have CREATE VIEW privilege on view table
+    - have some (SELECT/UPDATE/INSERT/DELETE) privileges on columns of
+    underlying tables used on top of SELECT list (because it can be
+    (theoretically) updated, so it is enough to have UPDATE privilege on
+    them, for example)
+    - have SELECT privilege on columns used in expressions of VIEW select
+    - for columns of underly tables used on top of SELECT list also will be
+    checked that we have not more privileges on correspondent column of view
+    table (i.e. user will not get some privileges by view creation)
+  */
   if (check_access(thd, CREATE_VIEW_ACL, view->db, &view->grant.privilege,
                    0, 0) ||
       grant_option && check_grant(thd, CREATE_VIEW_ACL, view, 0, 1, 0))
@@ -89,7 +101,7 @@ int mysql_create_view(THD *thd,
     for (tbl= sl->get_table_list(); tbl; tbl= tbl->next_local)
     {
       /*
-        Ensure that we have some privilage on this table, more strict check
+        Ensure that we have some privileges on this table, more strict check
         will be done on column level after preparation,
       */
       if (check_some_access(thd, VIEW_ANY_ACL, tbl))
@@ -103,16 +115,20 @@ int mysql_create_view(THD *thd,
                         tbl->real_name);
         DBUG_RETURN(-1);
       }
-      /* mark this table as table which will be checked after preparation */
+      /*
+        Mark this table as a table which will be checked after the prepare
+        phase
+      */
       tbl->table_in_first_from_clause= 1;
 
       /*
-        We need to check only SELECT_ACL for all normal fields, fields
-        where we need any privilege will be marked later
+        We need to check only SELECT_ACL for all normal fields, fields for
+        which we need "any" (SELECT/UPDATE/INSERT/DELETE) privilege will be
+        checked later
       */
       tbl->grant.want_privilege= SELECT_ACL;
       /*
-        Make sure that all rights are loaded to table 'grant' field.
+        Make sure that all rights are loaded to the TABLE::grant field.
 
         tbl->real_name will be correct name of table because VIEWs are
         not opened yet.
@@ -140,7 +156,7 @@ int mysql_create_view(THD *thd,
     }
   }
   /*
-    Mark fields for special privilege check (any privilege)
+    Mark fields for special privilege check ("any" privilege)
   */
   for (sl= select_lex; sl; sl= sl->next_select())
   {
@@ -169,14 +185,14 @@ int mysql_create_view(THD *thd,
     }
 
     /*
-      Copy privileges of underlaying VIEWs which was filled by
+      Copy the privileges of the underlying VIEWs which were filled by
       fill_effective_table_privileges
-      (they was not copied in derived tables processing)
+      (they were not copied at derived tables processing)
     */
     tbl->table->grant.privilege= tbl->grant.privilege;
   }
 
-  // prepare select to resolve all fields
+  /* prepare select to resolve all fields */
   lex->view_prepare_mode= 1;
   if (unit->prepare(thd, 0, 0))
   {
@@ -227,7 +243,7 @@ int mysql_create_view(THD *thd,
 
 #ifndef NO_EMBEDDED_ACCESS_CHECKS
   /*
-    Compare/check grants on view with grants of underlaying tables
+    Compare/check grants on view with grants of underlying tables
   */
   for (sl= select_lex; sl; sl= sl->next_select())
   {
@@ -245,7 +261,7 @@ int mysql_create_view(THD *thd,
       if ((fld= item->filed_for_view_update()))
       {
         /*
-          Do we have more privilegeson view field then underlying table field
+          Do we have more privileges on view field then underlying table field?
         */
         if ((~fld->have_privileges & priv))
         {
@@ -354,7 +370,7 @@ static int mysql_register_view(THD *thd, TABLE_LIST *view,
   LEX_STRING dir, file;
   DBUG_ENTER("mysql_register_view");
 
-  // print query
+  /* print query */
   str.length(0);
   {
     ulong sql_mode= thd->variables.sql_mode & MODE_ANSI_QUOTES;
@@ -365,7 +381,7 @@ static int mysql_register_view(THD *thd, TABLE_LIST *view,
   str.append('\0');
   DBUG_PRINT("VIEW", ("View: %s", str.ptr()));
 
-  // print file name
+  /* print file name */
   (void) my_snprintf(dir_buff, FN_REFLEN, "%s/%s/",
 		     mysql_data_home, view->db);
   unpack_filename(dir_buff, dir_buff);
@@ -379,7 +395,7 @@ static int mysql_register_view(THD *thd, TABLE_LIST *view,
   if (!view->timestamp.str)
     view->timestamp.str= view->timestamp_buffer;
 
-  // check old .frm
+  /* check old .frm */
   {
     char path_buff[FN_REFLEN];
     LEX_STRING path;
@@ -411,7 +427,7 @@ static int mysql_register_view(THD *thd, TABLE_LIST *view,
       /*
         read revision number
 
-        TODO: read dependense list, too, to process cascade/restrict
+        TODO: read dependence list, too, to process cascade/restrict
         TODO: special cascade/restrict procedure for alter?
       */
       if (parser->parse((gptr)view, &thd->mem_root,
@@ -429,7 +445,7 @@ static int mysql_register_view(THD *thd, TABLE_LIST *view,
       }
     }
   }
-  // fill structure
+  /* fill structure */
   view->query.str= (char*)str.ptr();
   view->query.length= str.length()-1; // we do not need last \0
   view->source.str= thd->query;
@@ -451,7 +467,7 @@ static int mysql_register_view(THD *thd, TABLE_LIST *view,
   if ((view->updatable_view= (can_be_merged &&
                               view->algorithm != VIEW_ALGORITHM_TMPTABLE)))
   {
-    // TODO: change here when we will support UNIONs
+    /* TODO: change here when we will support UNIONs */
     for (TABLE_LIST *tbl= (TABLE_LIST *)thd->lex->select_lex.table_list.first;
          tbl;
          tbl= tbl->next_local)
@@ -491,7 +507,6 @@ static int mysql_register_view(THD *thd, TABLE_LIST *view,
   RETURN
     0 ok
     1 error
-
 */
 
 my_bool
@@ -632,7 +647,7 @@ mysql_make_view(File_parser *parser, TABLE_LIST *table)
 
     /*
       check rights to run commands (EXPLAIN SELECT & SHOW CREATE) which show
-      underlaying tables
+      underlying tables
     */
     if ((old_lex->sql_command == SQLCOM_SELECT && old_lex->describe))
     {
@@ -682,7 +697,7 @@ mysql_make_view(File_parser *parser, TABLE_LIST *table)
     /*
       check MERGE algorithm ability
       - algorithm is not explicit TEMPORARY TABLE
-      - VIEW SELECT allow marging
+      - VIEW SELECT allow merging
       - VIEW used in subquery or command support MERGE algorithm
     */
     if (table->algorithm != VIEW_ALGORITHM_TMPTABLE &&
@@ -705,7 +720,7 @@ mysql_make_view(File_parser *parser, TABLE_LIST *table)
       /*
         next table should include SELECT_LEX under this table SELECT_LEX
 
-        TODO: ehere should be loop for multi tables substitution
+        TODO: here should be loop for multi tables substitution
       */
       table->ancestor->select_lex= table->select_lex;
       /*
@@ -714,7 +729,7 @@ mysql_make_view(File_parser *parser, TABLE_LIST *table)
       */
       view_tables->lock_type= table->lock_type;
 
-      /* Store WHERE clause for postprocessing in setup_ancestor */
+      /* Store WHERE clause for post-processing in setup_ancestor */
       table->where= lex->select_lex.where;
 
       /*
@@ -866,6 +881,13 @@ frm_type_enum mysql_frm_type(char *path)
     thd     thread handler
     view    view for check with opened table
 
+  DESCRIPTION
+    check that undertlaying table of viey contain one of following:
+      1) primary key of underlying table
+      2) unique key underlying table with fields for which NULL value is
+         impossible
+      3) all fields of underlying table
+
   RETURN
     FALSE   OK
     TRUE    view do not contain key or all fields
@@ -935,7 +957,7 @@ bool check_key_in_view(THD *thd, TABLE_LIST *view)
           0 == NO     ; Don't give any errors
           1 == YES    ; Give always an error
           2 == LIMIT1 ; Give an error if this is used with LIMIT 1
-                        This is used to protect against gui programs that
+                        This is used to protect against GUI programs that
                         uses LIMIT 1 to update just the current row. This
                         doesn't work reliable if the view doesn't have a
                         unique key or if the view doesn't use all fields in
diff --git a/sql/sql_yacc.yy b/sql/sql_yacc.yy
index 6e4893accb4..7b71f8ccca2 100644
--- a/sql/sql_yacc.yy
+++ b/sql/sql_yacc.yy
@@ -2423,8 +2423,8 @@ create_select:
 	    else if (lex->sql_command == SQLCOM_REPLACE)
 	      lex->sql_command= SQLCOM_REPLACE_SELECT;
 	    /*
-	      following work only with local list, global list is
-	      created correctly in this case
+              The following work only with the local list, the global list
+              is created correctly in this case
 	    */
 	    lex->current_select->table_list.save_and_clear(&lex->save_list);
 	    mysql_init_select(lex);
@@ -2437,8 +2437,8 @@ create_select:
 	  opt_select_from
 	  {
 	    /*
-	      following work only with local list, global list is
-	      created correctly in this case
+              The following work only with the local list, the global list
+              is created correctly in this case
 	    */
 	    Lex->current_select->table_list.push_front(&Lex->save_list);
 	  }
diff --git a/sql/table.cc b/sql/table.cc
index a9699fe0228..666effc75e7 100644
--- a/sql/table.cc
+++ b/sql/table.cc
@@ -169,7 +169,7 @@ int openfrm(THD *thd, const char *name, const char *alias, uint db_stat,
   outparam->db_record_offset=1;
   if (db_create_options & HA_OPTION_LONG_BLOB_PTR)
     outparam->blob_ptr_size=portable_sizeof_char_ptr;
-  /* Set temporaryly a good value for db_low_byte_first */
+  /* Set temporarily a good value for db_low_byte_first */
   outparam->db_low_byte_first=test(outparam->db_type != DB_TYPE_ISAM);
   error=4;
   outparam->max_rows=uint4korr(head+18);
@@ -710,7 +710,7 @@ int openfrm(THD *thd, const char *name, const char *alias, uint db_stat,
     outparam->blob_field=
       (Field_blob**) (outparam->field+outparam->fields); // Point at null ptr
 
-  /* The table struct is now initialzed;  Open the table */
+  /* The table struct is now initialized;  Open the table */
   error=2;
   if (db_stat)
   {
@@ -759,7 +759,7 @@ int openfrm(THD *thd, const char *name, const char *alias, uint db_stat,
   my_pthread_setspecific_ptr(THR_MALLOC,old_root);
   frm_error(error,outparam,name,ME_ERROR+ME_WAITTANG);
   delete outparam->file;
-  outparam->file=0;				// For easyer errorchecking
+  outparam->file=0;				// For easier errorchecking
   outparam->db_stat=0;
   hash_free(&outparam->name_hash);
   free_root(&outparam->mem_root,MYF(0));
@@ -788,7 +788,7 @@ int closefrm(register TABLE *table)
     table->fields=0;
   }
   delete table->file;
-  table->file=0;				/* For easyer errorchecking */
+  table->file=0;				/* For easier errorchecking */
   hash_free(&table->name_hash);
   free_root(&table->mem_root,MYF(0));
   DBUG_RETURN(error);
@@ -985,7 +985,7 @@ static void frm_error(int error, TABLE *form, const char *name, myf errortype)
 
 	/*
 	** fix a str_type to a array type
-	** typeparts sepearated with some char. differents types are separated
+	** typeparts separated with some char. differents types are separated
 	** with a '\0'
 	*/
 
@@ -1072,7 +1072,7 @@ static uint find_field(TABLE *form,uint start,uint length)
 }
 
 
-	/* Check that the integer is in the internvall */
+	/* Check that the integer is in the internal */
 
 int set_zone(register int nr, int min_zone, int max_zone)
 {
@@ -1136,7 +1136,7 @@ void append_unescaped(String *res, const char *pos, uint length)
       res->append('n');
       break;
     case '\r':
-      res->append('\\');		/* This gives better readbility */
+      res->append('\\');		/* This gives better readability */
       res->append('r');
       break;
     case '\\':
@@ -1500,15 +1500,17 @@ void st_table_list::set_ancestor()
     thd		- thread handler
     conds       - condition of this JOIN
 
+  DESCRIPTION
+    It is:
+    - preparing translation table for view columns (fix_fields() for every
+    call and creation for first call)
+    - preparing WHERE, ON and CHECK OPTION condition (fix_fields() for every
+    call and merging for first call).
+    If there are underlying view(s) procedure first will be called for them.
+
   RETURN
     0 - OK
     1 - error
-
-  TODO: for several substituted table last set up table (or maybe subtree,
-  it depends on future join implementation) will contain all fields of VIEW
-  (to be able call fix_fields() for them. All other will looks like empty
-  (without fields) for name resolving, but substituted expressions will
-  return correct used tables mask.
 */
 
 bool st_table_list::setup_ancestor(THD *thd, Item **conds)
@@ -1619,7 +1621,7 @@ bool st_table_list::setup_ancestor(THD *thd, Item **conds)
         {
           /*
             Store WHERE condition to ON expression for outer join, because
-            we can't use WHERE to correctly execute jeft joins on VIEWs and
+            we can't use WHERE to correctly execute left joins on VIEWs and
             this expression will not be moved to WHERE condition (i.e. will
             be clean correctly for PS/SP)
           */
@@ -1633,7 +1635,7 @@ bool st_table_list::setup_ancestor(THD *thd, Item **conds)
         {
           /*
             Store WHERE condition to ON expression for outer join, because
-            we can't use WHERE to correctly execute jeft joins on VIEWs and
+            we can't use WHERE to correctly execute left joins on VIEWs and
             this expression will not be moved to WHERE condition (i.e. will
             be clean correctly for PS/SP)
           */
diff --git a/sql/table.h b/sql/table.h
index ddc21261e48..b5d55f257c3 100644
--- a/sql/table.h
+++ b/sql/table.h
@@ -34,7 +34,7 @@ typedef struct st_order {
   bool	 asc;				/* true if ascending */
   bool	 free_me;			/* true if item isn't shared  */
   bool	 in_field_list;			/* true if in select field list */
-  bool   counter_used;                  /* parapeter was counter of columns */
+  bool   counter_used;                  /* parameter was counter of columns */
   Field  *field;			/* If tmp-table group */
   char	 *buff;				/* If tmp-table group */
   table_map used,depend_map;
@@ -116,7 +116,7 @@ struct st_table {
     These two members hold offset in record + 1 for TIMESTAMP field
     with NOW() as default value or/and with ON UPDATE NOW() option. 
     If 0 then such field is absent in this table or auto-set for default
-    or/and on update should be temporaly disabled for some reason.
+    or/and on update should be temporally disabled for some reason.
     These values is setup to offset value for each statement in open_table()
     and turned off in statement processing code (see mysql_update as example).
   */
@@ -235,10 +235,10 @@ typedef struct st_table_list
   Item          *where;                 /* VIEW WHERE clause condition */
   Item          *check_option;          /* WITH CHECK OPTION condition */
   LEX_STRING	query;			/* text of (CRETE/SELECT) statement */
-  LEX_STRING	md5;			/* md5 of query tesxt */
+  LEX_STRING	md5;			/* md5 of query text */
   LEX_STRING	source;			/* source of CREATE VIEW */
-  LEX_STRING	view_db;		/* save view database */
-  LEX_STRING	view_name;		/* save view name */
+  LEX_STRING	view_db;		/* saved view database */
+  LEX_STRING	view_name;		/* saved view name */
   LEX_STRING	timestamp;		/* GMT time stamp of last operation */
   ulonglong	file_version;		/* version of file's field set */
   ulonglong     updatable_view;         /* VIEW can be updated */
@@ -263,11 +263,11 @@ typedef struct st_table_list
   st_table_list *embedding;             /* nested join containing the table */
   List<struct st_table_list> *join_list;/* join list the table belongs to   */
   bool		cacheable_table;	/* stop PS caching */
-  /* used in multi-upd/views privelege check */
+  /* used in multi-upd/views privilege check */
   bool		table_in_first_from_clause;
   bool		skip_temporary;		/* this table shouldn't be temporary */
   bool          setup_is_done;          /* setup_tables() is done */
-  /* do view contain auto_increment field */
+  /* TRUE if this merged view contain auto_increment field */
   bool          contain_auto_increment;
   /* FRMTYPE_ERROR if any type is acceptable */
   enum frm_type_enum required_type;