row0mysql.c:

  Allow always DROPping of a table which is only referenced by FOREIGN KEY constraints from the same table
Many files:
  Do not let REPLACE to perform internally an UPDATE if the table is referenced by a FOREIGN KEY: the manual says that REPLACE must resolve a duplicate key error semantically with DELETE(s) + INSERT, and not by an UPDATE; the internal update caused foreign key checks and cascaded operations to behave in a semantically wrong way

1 files changed, 2 insertions, 0 deletions

diff --git a/sql/handler.h b/sql/handler.h
index 60edf539e2c..750db45759e 100644
--- a/sql/handler.h
+++ b/sql/handler.h
@@ -319,6 +319,8 @@ public:
   virtual void append_create_info(String *packet) {}
   virtual char* get_foreign_key_create_info()
   { return(NULL);}  /* gets foreign key create string from InnoDB */
+  virtual uint referenced_by_foreign_key() { return 0;} /* used in REPLACE;
+		    is > 0 if table is referred by a FOREIGN KEY */
   virtual void init_table_handle_for_HANDLER()
   { return; }       /* prepare InnoDB for HANDLER */  
   virtual void free_foreign_key_create_info(char* str) {}