Fix wrong merge of commit d218d1a

Author: cvicentiu

mysql-test/r/index_merge_innodb.result

@@ -815,8 +815,6 @@ SET @save_sort_buffer_size=@@sort_buffer_size;
 SET @save_innodb_file_format= @@innodb_file_format;
 SET @save_innodb_large_prefix= @@innodb_large_prefix;
 SET sort_buffer_size=2048;
-SET GLOBAL innodb_file_format = BARRACUDA;
-SET GLOBAL innodb_large_prefix = ON;
 CREATE TABLE t1 (
 a VARCHAR(1024) CHARACTER SET UTF8 PRIMARY KEY,
 b INT,
@@ -826,15 +824,13 @@ INDEX (b)
 INSERT INTO t1 SELECT seq, seq, seq from seq_1_to_100;
 EXPLAIN SELECT * FROM t1 WHERE a='1' OR b < 5;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	index_merge	PRIMARY,b	b,PRIMARY	5,3074	NULL	4	Using sort_union(b,PRIMARY); Using where
+1	SIMPLE	t1	index_merge	PRIMARY,b	b,PRIMARY	5,3074	NULL	5	Using sort_union(b,PRIMARY); Using where
 SELECT * FROM t1 WHERE a='1' OR b < 5;
 a	b	c
 2	2	2
 3	3	3
 4	4	4
 1	1	1
 DROP TABLE t1;
-SET GLOBAL innodb_file_format = @save_innodb_file_format;
-SET GLOBAL innodb_large_prefix = @save_innodb_large_prefix;
 SET sort_buffer_size= @save_sort_buffer_size;
 disconnect disable_purge;

mysql-test/t/index_merge_innodb.test

@@ -208,8 +208,6 @@ SET @save_sort_buffer_size=@@sort_buffer_size;
 SET @save_innodb_file_format= @@innodb_file_format;
 SET @save_innodb_large_prefix= @@innodb_large_prefix;
 SET sort_buffer_size=2048;
-SET GLOBAL innodb_file_format = BARRACUDA;
-SET GLOBAL innodb_large_prefix = ON;
 
 CREATE TABLE t1 (
   a VARCHAR(1024) CHARACTER SET UTF8 PRIMARY KEY,
@@ -222,8 +220,6 @@ EXPLAIN SELECT * FROM t1 WHERE a='1' OR b < 5;
 SELECT * FROM t1 WHERE a='1' OR b < 5;
 DROP TABLE t1;
 
-SET GLOBAL innodb_file_format = @save_innodb_file_format;
-SET GLOBAL innodb_large_prefix = @save_innodb_large_prefix;
 SET sort_buffer_size= @save_sort_buffer_size;
 
 disconnect disable_purge;

sql/uniques.h

@@ -85,6 +85,9 @@ class Unique :public Sql_alloc
   {
     size_t max_elems_in_tree=
       max_in_memory_size / ALIGN_SIZE(sizeof(TREE_ELEMENT)+key_size);
+
+    if (max_elems_in_tree == 0)
+      max_elems_in_tree= 1;
     return (int) (sizeof(uint)*(1 + nkeys/max_elems_in_tree));
   }