branches/5.1: Fix bug #47621 "MySQL and InnoDB data dictionaries

will become out of sync when renaming columns". MySQL does not
provide new column name information to storage engine to
update the system table. To avoid column name mismatch, we shall
just request a table copy for now.

rb://246 approved by Marko.

handler/ha_innodb.cc

@@ -8489,6 +8489,44 @@ innobase_set_cursor_view(
 				  (cursor_view_t*) curview);
 }
 
+/***********************************************************************
+If col_name is not NULL, check whether the named column is being
+renamed in the table. If col_name is not provided, check
+whether any one of columns in the table is being renamed. */
+static
+bool
+check_column_being_renamed(
+/*=======================*/
+					/* out: true if find the column
+					being renamed */
+	const TABLE*	table,		/* in: MySQL table */
+	const char*	col_name)	/* in: name of the column */
+{
+	uint		k;
+	Field*		field;
+
+	for (k = 0; k < table->s->fields; k++) {
+		field = table->field[k];
+
+		if (field->flags & FIELD_IS_RENAMED) {
+
+			/* If col_name is not provided, return
+			if the field is marked as being renamed. */
+			if (!col_name) {
+				return(true);
+			}
+
+			/* If col_name is provided, return only
+			if names match */
+			if (innobase_strcasecmp(field->field_name,
+						col_name) == 0) {
+				return(true);
+			}
+		}
+	}
+
+	return(false);
+}
 
 /***********************************************************************
 Check whether any of the given columns is being renamed in the table. */
@@ -8503,21 +8541,12 @@ column_is_being_renamed(
 	const char**	col_names)	/* in: names of the columns */
 {
 	uint		j;
-	uint		k;
-	Field*		field;
-	const char*	col_name;
 
 	for (j = 0; j < n_cols; j++) {
-		col_name = col_names[j];
-		for (k = 0; k < table->s->fields; k++) {
-			field = table->field[k];
-			if ((field->flags & FIELD_IS_RENAMED)
-			    && innobase_strcasecmp(field->field_name,
-						   col_name) == 0) {
+		if (check_column_being_renamed(table, col_names[j])) {
 			return(true);
 		}
 	}
-	}
 
 	return(false);
 }
@@ -8597,6 +8626,15 @@ bool ha_innobase::check_if_incompatible_data(
 		return COMPATIBLE_DATA_NO;
 	}
 
+	/* For column rename operation, MySQL does not supply enough
+	information (new column name etc.) for InnoDB to make appropriate
+	system metadata change. To avoid system metadata inconsistency,
+	currently we can just request a table rebuild/copy by returning
+	COMPATIBLE_DATA_NO */
+	if (check_column_being_renamed(table, NULL)) {
+		return COMPATIBLE_DATA_NO;
+	}
+
 	/* Check if a column participating in a foreign key is being renamed.
 	There is no mechanism for updating InnoDB foreign key definitions. */
 	if (foreign_key_column_is_being_renamed(prebuilt, table)) {

mysql-test/innodb_bug21704.result

@@ -25,8 +25,8 @@ ALTER TABLE t1 CHANGE a c INT;
 ERROR HY000: Error on rename of '#sql-temporary' to './test/t1' (errno: 150)
 # Ensure that online column rename works.
 ALTER TABLE t1 CHANGE b c INT;
-affected rows: 0
-info: Records: 0  Duplicates: 0  Warnings: 0
+affected rows: 3
+info: Records: 3  Duplicates: 0  Warnings: 0
 
 # Test renaming the column in the referencing table
 
@@ -34,8 +34,8 @@ ALTER TABLE t2 CHANGE a c INT;
 ERROR HY000: Error on rename of '#sql-temporary' to './test/t2' (errno: 150)
 # Ensure that online column rename works.
 ALTER TABLE t2 CHANGE b c INT;
-affected rows: 0
-info: Records: 0  Duplicates: 0  Warnings: 0
+affected rows: 3
+info: Records: 3  Duplicates: 0  Warnings: 0
 
 # Test with self-referential constraints
 
@@ -45,8 +45,8 @@ ALTER TABLE t3 CHANGE b d INT;
 ERROR HY000: Error on rename of '#sql-temporary' to './test/t3' (errno: 150)
 # Ensure that online column rename works.
 ALTER TABLE t3 CHANGE c d INT;
-affected rows: 0
-info: Records: 0  Duplicates: 0  Warnings: 0
+affected rows: 3
+info: Records: 3  Duplicates: 0  Warnings: 0
 
 # Cleanup.
 

mysql-test/innodb_bug47621.result

+CREATE TABLE bug47621 (salesperson INT) ENGINE=InnoDB;
+ALTER TABLE bug47621 CHANGE salesperson sales_acct_id INT;
+create index orgs on bug47621(sales_acct_id);
+ALTER TABLE bug47621 CHANGE sales_acct_id salesperson INT;
+drop table bug47621;
+CREATE TABLE bug47621_sale (
+salesperson INT,
+PRIMARY KEY(salesperson)) engine = innodb;
+CREATE TABLE bug47621_shirt(
+id SMALLINT,
+owner INT,
+FOREIGN KEY(owner)
+references bug47621_sale(salesperson) ON DELETE RESTRICT)
+engine = innodb;
+insert into bug47621_sale values(9);
+insert into bug47621_shirt values(1, 9);
+ALTER TABLE bug47621_shirt CHANGE id new_id INT;
+drop table bug47621_shirt;
+ALTER TABLE bug47621_sale CHANGE salesperson sales_acct_id INT;
+ALTER TABLE bug47621_sale ADD INDEX idx (sales_acct_id);
+drop table bug47621_sale;

mysql-test/innodb_bug47621.test

+# This is the test for bug #47621, column rename operation should
+# not result in column definition inconsistency between MySQL and
+# InnoDB
+
+--source include/have_innodb.inc
+
+CREATE TABLE bug47621 (salesperson INT) ENGINE=InnoDB;
+
+# Change the column name
+ALTER TABLE bug47621 CHANGE salesperson sales_acct_id INT;
+
+# If there is inconsistency of column name definition
+# in MySQL or InnoDB, following create index would fail
+create index orgs on bug47621(sales_acct_id);
+
+# Change the column name back with the index defined on it.
+ALTER TABLE bug47621 CHANGE sales_acct_id salesperson INT;
+
+drop table bug47621;
+
+CREATE TABLE bug47621_sale (
+	salesperson INT,
+	PRIMARY KEY(salesperson)) engine = innodb;
+
+CREATE TABLE bug47621_shirt(
+	id SMALLINT,
+	owner INT,
+	FOREIGN KEY(owner)
+		 references bug47621_sale(salesperson) ON DELETE RESTRICT)
+	engine = innodb;
+
+insert into bug47621_sale values(9);
+
+insert into bug47621_shirt values(1, 9);
+
+# Any rename operation on columns involved in a reference constraint will
+# fail, as it will be rejected by InnoDB row_rename_table_for_mysql().
+# In above example, any rename on column "salesperson" for table
+# "bug47621_sale", or on column "owner" for table "bug47621_shirt will
+# be blocked. We do not put such rename in the test since InnoDB error
+# message will be printed in the error log, and result in test failure.
+#
+# ALTER TABLE bug47621_sale CHANGE salesperson sales_acct_id INT;
+
+# Any rename on columns not involved in the foreign key constraint
+# could still proceed
+ALTER TABLE bug47621_shirt CHANGE id new_id INT;
+
+# Referencing table dropped, the rename operation on related columns
+# could proceed
+drop table bug47621_shirt;
+
+ALTER TABLE bug47621_sale CHANGE salesperson sales_acct_id INT;
+
+ALTER TABLE bug47621_sale ADD INDEX idx (sales_acct_id);
+
+drop table bug47621_sale;