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


sql/ha_innodb.cc:
  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
sql/sql_insert.cc:
  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
sql/ha_innodb.h:
  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
sql/handler.h:
  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
innobase/dict/dict0dict.c:
  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
innobase/include/dict0dict.h:
  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
innobase/row/row0mysql.c:
  Allow always DROPping of a table which is only referenced by FOREIGN KEY constraints from the same table

1 files changed, 22 insertions, 1 deletions

diff --git a/sql/ha_innodb.cc b/sql/ha_innodb.cc
index 01af07f34ec..73f517285a0 100644
--- a/sql/ha_innodb.cc
+++ b/sql/ha_innodb.cc
@@ -4289,7 +4289,28 @@ ha_innobase::get_foreign_key_create_info(void)
         prebuilt->trx->op_info = (char*)"";
 
   	return(str);
-}			
+}
+
+/***********************************************************************
+Checks if a table is referenced by a foreign key. The MySQL manual states that
+a REPLACE is either equivalent to an INSERT, or DELETE(s) + INSERT. Only a
+delete is then allowed internally to resolve a duplicate key conflict in
+REPLACE, not an update. */
+
+uint
+ha_innobase::referenced_by_foreign_key(void)
+/*========================================*/
+			/* out: > 0 if referenced by a FOREIGN KEY */
+{
+	row_prebuilt_t* prebuilt = (row_prebuilt_t*)innobase_prebuilt;
+
+	if (dict_table_referenced_by_foreign_key(prebuilt->table)) {
+
+		return(1);
+	}
+
+	return(0);
+}
 
 /***********************************************************************
 Frees the foreign key create info for a table stored in InnoDB, if it is