bzr commit into mysql-5.1 branch (davi:2664) Bug#21704

[Davi Arnaut]

# At a local mysql-5.1 repository of davi

 2664 Davi Arnaut	2008-06-16
      Bug#21704: Renaming column does not update FK definition
            
      The problem was that renaming columns that appear in a foreign
      key definition does not cause the definition to be updated to
      the new column name. This occurred because the server was not
      notifying the storage engine of a possible incompatible change
      in column names.
      
      The solution is to iterate over the table fields and check
      if any of the columns were renamed. If a column was renamed,
      inform that it's not a data compatible change.
      
      It's important to note that this modification will cause a
      full table copy to take place when renaming columns on a InnoDB
      table.
modified:
  mysql-test/include/mix1.inc
  mysql-test/r/innodb_mysql.result
  storage/innobase/handler/ha_innodb.cc

per-file messages:
  mysql-test/include/mix1.inc
    Add test case for Bug#21704
  mysql-test/r/innodb_mysql.result
    Add test case result for Bug#21704
  storage/innobase/handler/ha_innodb.cc
    Iterate over the table fields checking if a column was renamed.
=== modified file 'mysql-test/include/mix1.inc'
--- a/mysql-test/include/mix1.inc	2008-05-20 07:38:17 +0000
+++ b/mysql-test/include/mix1.inc	2008-06-16 14:40:45 +0000
@@ -1453,4 +1453,33 @@ ALTER TABLE t1 CHANGE id id2 INT;
 DROP TABLE t2;
 DROP TABLE t1;
 
+#
+# Bug#21704: Renaming column does not update FK definition.
+#
+
+--disable_warnings
+DROP TABLE IF EXISTS t1;
+DROP TABLE IF EXISTS t2;
+--enable_warnings
+
+CREATE TABLE t1(id INT PRIMARY KEY NOT NULL)
+  ENGINE=innodb;
+
+CREATE TABLE t2(
+  t1_id INT PRIMARY KEY,
+  CONSTRAINT fk1 FOREIGN KEY (t1_id) REFERENCES t1(id))
+  ENGINE=innodb;
+
+--echo
+
+--disable_result_log
+--error ER_ERROR_ON_RENAME
+ALTER TABLE t1 CHANGE id id2 INT NOT NULL;
+--enable_result_log
+
+--echo
+
+DROP TABLE t2;
+DROP TABLE t1;
+
 --echo End of 5.1 tests

=== modified file 'mysql-test/r/innodb_mysql.result'
--- a/mysql-test/r/innodb_mysql.result	2008-05-07 05:58:21 +0000
+++ b/mysql-test/r/innodb_mysql.result	2008-06-16 14:40:45 +0000
@@ -1653,6 +1653,19 @@ ALTER TABLE t1 CHANGE id id2 INT;
 
 DROP TABLE t2;
 DROP TABLE t1;
+DROP TABLE IF EXISTS t1;
+DROP TABLE IF EXISTS t2;
+CREATE TABLE t1(id INT PRIMARY KEY NOT NULL)
+ENGINE=innodb;
+CREATE TABLE t2(
+t1_id INT PRIMARY KEY,
+CONSTRAINT fk1 FOREIGN KEY (t1_id) REFERENCES t1(id))
+ENGINE=innodb;
+
+ALTER TABLE t1 CHANGE id id2 INT NOT NULL;
+
+DROP TABLE t2;
+DROP TABLE t1;
 End of 5.1 tests
 drop table if exists t1, t2, t3;
 create table t1(a int);

=== modified file 'storage/innobase/handler/ha_innodb.cc'
--- a/storage/innobase/handler/ha_innodb.cc	2008-05-14 08:45:32 +0000
+++ b/storage/innobase/handler/ha_innodb.cc	2008-06-16 14:40:45 +0000
@@ -7943,6 +7943,19 @@ bool ha_innobase::check_if_incompatible_
 		return COMPATIBLE_DATA_NO;
 	}
 
+	/* Check that columns were not renamed, because there is no
+	mechanism for updating column names in the InnoDB data
+	dictionary (and in InnoDB foreign key definitions) when
+	column names are updated in the MySQL data dictionary. */
+	for (uint i= 0; i < table->s->fields; i++) {
+		Field *field= table->field[i];
+
+		if (field->flags & FIELD_IS_RENAMED) {
+
+			return COMPATIBLE_DATA_NO;
+		}
+	}
+		
 	return COMPATIBLE_DATA_YES;
 }