row0mysql.c, pars0pars.c, eval0eval.c, dict0load.c, dict0dict.c, dict0crea.c:

  Fix bug #3478: InnoDB's FOREIGN KEY tables treated table and database names as case-insensitive; RENAME TABLE t to T would hang in an endless loop if t had a foreign key constraint defined on it
dict0dict.c:
  Fix bug #3478: InnoDB's FOREIGN KEY tables treated table and database names as case-insensitive; RENAME TABLE t to T would hang in an endless loop if t had a foreign key constraint defined on it; fix also a hang that would occur if one tried in ALTER TABLE or RENAME TABLE to create a foreign key constraint name that collided with another existing name


innobase/dict/dict0crea.c:
  Fix bug #3478: InnoDB's FOREIGN KEY tables treated table and database names as case-insensitive; RENAME TABLE t to T would hang in an endless loop if t had a foreign key constraint defined on it
innobase/dict/dict0load.c:
  Fix bug #3478: InnoDB's FOREIGN KEY tables treated table and database names as case-insensitive; RENAME TABLE t to T would hang in an endless loop if t had a foreign key constraint defined on it
innobase/dict/dict0dict.c:
  Fix bug #3478: InnoDB's FOREIGN KEY tables treated table and database names as case-insensitive; RENAME TABLE t to T would hang in an endless loop if t had a foreign key constraint defined on it; fix also a hang that would occur if one tried in ALTER TABLE or RENAME TABLE to create a foreign key constraint name that collided with another existing name
innobase/eval/eval0eval.c:
  Fix bug #3478: InnoDB's FOREIGN KEY tables treated table and database names as case-insensitive; RENAME TABLE t to T would hang in an endless loop if t had a foreign key constraint defined on it
innobase/pars/pars0pars.c:
  Fix bug #3478: InnoDB's FOREIGN KEY tables treated table and database names as case-insensitive; RENAME TABLE t to T would hang in an endless loop if t had a foreign key constraint defined on it
innobase/row/row0mysql.c:
  Fix bug #3478: InnoDB's FOREIGN KEY tables treated table and database names as case-insensitive; RENAME TABLE t to T would hang in an endless loop if t had a foreign key constraint defined on it

3 files changed, 35 insertions, 6 deletions

diff --git a/innobase/dict/dict0crea.c b/innobase/dict/dict0crea.c
index 31a601e68b0..e8261ab1e91 100644
--- a/innobase/dict/dict0crea.c
+++ b/innobase/dict/dict0crea.c
@@ -1011,6 +1011,12 @@ dict_create_or_check_foreign_constraint_tables(void)
 	there are 2 secondary indexes on SYS_FOREIGN, and they
 	are defined just like below */
 	
+	/* NOTE: when designing InnoDB's foreign key support in 2001, we made
+	an error and made the table names and the foreign key id of type
+	'CHAR' (internally, really a VARCHAR). We should have made the type
+	VARBINARY, like in other InnoDB system tables, to get a clean
+	design. */
+
 	str = (char *)
 	"PROCEDURE CREATE_FOREIGN_SYS_TABLES_PROC () IS\n"
 	"BEGIN\n"
@@ -1227,9 +1233,17 @@ loop:
 		fputs(".\nA foreign key constraint of name ", ef);
 		ut_print_name(ef, foreign->id);
 		fputs("\nalready exists."
-			"  (Note that internally InnoDB adds 'databasename/'\n"
+			" (Note that internally InnoDB adds 'databasename/'\n"
 			"in front of the user-defined constraint name).\n",
 			ef);
+		fputs("Note that InnoDB's FOREIGN KEY system tables store\n"
+		      "constraint names as case-insensitive, with the\n"
+		      "MySQL standard latin1_swedish_ci collation. If you\n"
+		      "create tables or databases whose names differ only in\n"
+		      "the character case, then collisions in constraint\n"
+		      "names can occur. Workaround: name your constraints\n"
+		      "explicitly with unique names.\n",
+			ef);
 
 		mutex_exit(&dict_foreign_err_mutex);
 
diff --git a/innobase/dict/dict0dict.c b/innobase/dict/dict0dict.c
index 4340934ab3d..5ca31ecd422 100644
--- a/innobase/dict/dict0dict.c
+++ b/innobase/dict/dict0dict.c
@@ -132,7 +132,7 @@ dict_index_build_internal_non_clust(
 	dict_index_t*	index);	/* in: user representation of a non-clustered
 				index */	
 /**************************************************************************
-Removes a foreign constraint struct from the dictionet cache. */
+Removes a foreign constraint struct from the dictionary cache. */
 static
 void
 dict_foreign_remove_from_cache(
@@ -581,7 +581,7 @@ dict_table_get_on_id(
 	dict_table_t*	table;
 	
 	if (ut_dulint_cmp(table_id, DICT_FIELDS_ID) <= 0
-	   || trx->dict_operation) {
+	   || trx->dict_operation_lock_mode == RW_X_LATCH) {
 		/* It is a system table which will always exist in the table
 		cache: we avoid acquiring the dictionary mutex, because
 		if we are doing a rollback to handle an error in TABLE
diff --git a/innobase/dict/dict0load.c b/innobase/dict/dict0load.c
index 6a4d4c86824..a4637e09d07 100644
--- a/innobase/dict/dict0load.c
+++ b/innobase/dict/dict0load.c
@@ -19,6 +19,7 @@ Created 4/24/1996 Heikki Tuuri
 #include "mach0data.h"
 #include "dict0dict.h"
 #include "dict0boot.h"
+#include "rem0cmp.h"
 
 /************************************************************************
 Finds the first table name in the given database. */
@@ -1121,12 +1122,26 @@ loop:
 	rec = btr_pcur_get_rec(&pcur);
 	field = rec_get_nth_field(rec, 0, &len);
 
-	/* Check if the table name in record is the one searched for */
-	if (len != ut_strlen(table_name)
-	    || 0 != ut_memcmp(field, table_name, len)) {
+	/* Check if the table name in the record is the one searched for; the
+	following call does the comparison in the latin1_swedish_ci
+	charset-collation, in a case-insensitive way. */
 
+	if (0 != cmp_data_data(dfield_get_type(dfield),
+			dfield_get_data(dfield), dfield_get_len(dfield),
+			field, len)) {
+		
 		goto load_next_index;
 	}
+
+	/* Since table names in SYS_FOREIGN are stored in a case-insensitive
+	order, we have to check that the table name matches also in a binary
+	string comparison. On Unix, MySQL allows table names that only differ
+	in character case. */
+
+	if (0 != ut_memcmp(field, table_name, len)) {
+
+		goto next_rec;
+	}
 		
 	if (rec_get_deleted_flag(rec)) {