Many files:

  Push the patch of Jan Lindstrom: better comments
ha_innodb.cc:
  Partial fix for Bug #12263 : we let InnoDB always to perform a rollback on the trx object if MySQL closes a connection; but we do print a warning to the .err log if an InnoDB transaction was active; we may remove that print later, since the situation really is not a bug; MySQL just is not aware that some cursor operation started an InnoDB transaction


sql/ha_innodb.cc:
  Partial fix for Bug #12263 : we let InnoDB always to perform a rollback on the trx object if MySQL closes a connection; but we do print a warning to the .err log if an InnoDB transaction was active; we may remove that print later, since the situation really is not a bug; MySQL just is not aware that some cursor operation started an InnoDB transaction
sql/ha_innodb.h:
  Push the patch of Jan Lindstrom: better comments
innobase/trx/trx0trx.c:
  Push the patch of Jan Lindstrom: better comments
innobase/srv/srv0srv.c:
  Push the patch of Jan Lindstrom: better comments
innobase/srv/srv0start.c:
  Push the patch of Jan Lindstrom: better comments
innobase/row/row0sel.c:
  Push the patch of Jan Lindstrom: better comments
innobase/read/read0read.c:
  Push the patch of Jan Lindstrom: better comments
innobase/include/read0read.h:
  Push the patch of Jan Lindstrom: better comments
innobase/include/trx0trx.h:
  Push the patch of Jan Lindstrom: better comments

1 files changed, 12 insertions, 9 deletions

diff --git a/sql/ha_innodb.h b/sql/ha_innodb.h
index 2cbc1c8d91b..3bc1fc5b2c8 100644
--- a/sql/ha_innodb.h
+++ b/sql/ha_innodb.h
@@ -302,7 +302,7 @@ which is in the prepared state */
 
 int innobase_rollback_by_xid(
 			/* out: 0 or error number */
-	XID	*xid);	/* in : X/Open XA Transaction Idenfification */
+	XID	*xid);	/* in : X/Open XA Transaction Identification */
 
 
 int innobase_xa_end(THD *thd);
@@ -312,9 +312,10 @@ int innobase_repl_report_sent_binlog(THD *thd, char *log_file_name,
                                my_off_t end_offset);
 
 /***********************************************************************
-This function creates a consistent view for a cursor and start a transaction
-if it has not been started. This consistent view is then used inside of MySQL 
-when accesing records using a cursor. */
+Create a consistent view for a cursor based on current transaction
+which is created if the corresponding MySQL thread still lacks one.
+This consistent view is then used inside of MySQL when accessing records 
+using a cursor. */
 
 void*
 innobase_create_cursor_view(void);
@@ -322,9 +323,9 @@ innobase_create_cursor_view(void);
 				/* out: Pointer to cursor view or NULL */
 
 /***********************************************************************
-This function closes the given consistent cursor view. Note that
-global read view is restored to a transaction and a transaction is
-started if it has not been started. */
+Close the given consistent cursor view of a transaction and restore
+global read view to a transaction read view. Transaction is created if the 
+corresponding MySQL thread still lacks one. */
 
 void
 innobase_close_cursor_view(
@@ -332,8 +333,10 @@ innobase_close_cursor_view(
 	void*	curview);	/* in: Consistent read view to be closed */
 
 /***********************************************************************
-This function sets the given consistent cursor view to a transaction.
-If a transaction does not exist, transaction is started. */
+Set the given consistent cursor view to a transaction which is created 
+if the corresponding MySQL thread still lacks one. If the given 
+consistent cursor view is NULL global read view of a transaction is
+restored to a transaction read view. */
 
 void
 innobase_set_cursor_view(