cleanup: fix a comment

Author: vuvova

include/my_base.h

@@ -566,7 +566,7 @@ typedef ulong key_part_map;
 #define HA_STATE_KEY_CHANGED	128
 #define HA_STATE_WRITE_AT_END	256	/* set in _ps_find_writepos */
 #define HA_STATE_BUFF_SAVED	512	/* If current keybuff is info->buff */
-#define HA_STATE_ROW_CHANGED	1024	/* To invalide ROW cache */
+#define HA_STATE_ROW_CHANGED	1024	/* To invalidate ROW cache */
 #define HA_STATE_EXTEND_BLOCK	2048
 #define HA_STATE_RNEXT_SAME	4096	/* rnext_same occupied lastkey2 */
 

sql/sql_parse.cc

@@ -4167,15 +4167,15 @@ mysql_execute_command(THD *thd)
     DBUG_ASSERT(select_lex->offset_limit == 0);
     unit->set_limit(select_lex);
     MYSQL_UPDATE_START(thd->query());
-    res= (up_result= mysql_update(thd, all_tables,
+    res= up_result= mysql_update(thd, all_tables,
                                   select_lex->item_list,
                                   lex->value_list,
                                   select_lex->where,
                                   select_lex->order_list.elements,
                                   select_lex->order_list.first,
                                   unit->select_limit_cnt,
                                   lex->duplicates, lex->ignore,
-                                  &found, &updated));
+                                  &found, &updated);
     MYSQL_UPDATE_DONE(res, found, updated);
     /* mysql_update return 2 if we need to switch to multi-update */
     if (up_result != 2)

sql/sql_select.cc

@@ -1926,7 +1926,7 @@ JOIN::optimize_inner()
   /*
     It's necessary to check const part of HAVING cond as
     there is a chance that some cond parts may become
-    const items after make_join_statisctics(for example
+    const items after make_join_statistics(for example
     when Item is a reference to cost table field from
     outer join).
     This check is performed only for those conditions

sql/structs.h

@@ -64,9 +64,11 @@ typedef struct st_keyfile_info {	/* used with ha_info() */
 
 
 typedef struct st_key_part_info {	/* Info about a key part */
-  Field *field;
-  uint	offset;				/* offset in record (from 0) */
-  uint	null_offset;			/* Offset to null_bit in record */
+  Field *field;                         /* the Field object for the indexed
+                                           prefix of the original table Field.
+                                           NOT necessarily the original Field */
+  uint  offset;                         /* Offset in record (from 0) */
+  uint  null_offset;                    /* Offset to null_bit in record */
   /* Length of key part in bytes, excluding NULL flag and length bytes */
   uint16 length;
   /* 
@@ -77,9 +79,8 @@ typedef struct st_key_part_info {	/* Info about a key part */
   */
   uint16 store_length;
   uint16 key_type;
-  /* Fieldnr begins counting from 1 */
-  uint16 fieldnr;			/* Fieldnum in UNIREG */
-  uint16 key_part_flag;			/* 0 or HA_REVERSE_SORT */
+  uint16 fieldnr;                       /* Fieldnr begins counting from 1 */
+  uint16 key_part_flag;                 /* 0 or HA_REVERSE_SORT */
   uint8 type;
   uint8 null_bit;			/* Position to null_bit */
 } KEY_PART_INFO ;

sql/table.cc

@@ -2674,10 +2674,10 @@ static bool fix_and_check_vcol_expr(THD *thd, TABLE *table, Field *field,
     Unpack the definition of a virtual column from its linear representation
 
   @param thd             The thread object
-  @param mem_root	 Where to allocate memory
+  @param mem_root        Where to allocate memory
   @param table           The table containing the virtual column
+  @param field           Field if this is a DEFAULT or AS, otherwise NULL
   @param vcol            The Virtual_column object
-  @param field	         Field if this is a DEFAULT or AS, otherwise NULL
   @param[out] error_reported   Flag to inform the caller that no
                                other error messages are to be generated
 
@@ -2696,10 +2696,8 @@ static bool fix_and_check_vcol_expr(THD *thd, TABLE *table, Field *field,
     Before passing 'vcol_expr' to the parser the function wraps it in
     parentheses and prepends a special keyword.
   
-   @retval
-     Virtual_column_info*   If a success
-   @retval
-     NULL                    Error
+   @retval Virtual_column_info*   Success
+   @retval NULL                   Error
 */
 
 Virtual_column_info *unpack_vcol_info_from_frm(THD *thd,
@@ -2820,10 +2818,6 @@ static bool check_vcol_forward_refs(Field *field, Virtual_column_info *vcol)
   return res;
 }
 
-/*
-  Read data from a binary .frm file from MySQL 3.23 - 5.0 into TABLE_SHARE
-*/
-
 /*
   Open a table based on a TABLE_SHARE