DESC sys.schema_redundant_indexes;
Field	Type	Null	Key	Default	Extra
table_schema	varchar(64)	NO
table_name	varchar(64)	NO
redundant_index_name	varchar(64)	NO
redundant_index_columns	text	YES		NULL
redundant_index_non_unique	bigint(1)	YES		NULL
dominant_index_name	varchar(64)	NO
dominant_index_columns	text	YES		NULL
dominant_index_non_unique	bigint(1)	YES		NULL
subpart_exists	int(1)	NO		0
sql_drop_index	varchar(223)	YES		NULL
SELECT * FROM sys.schema_redundant_indexes;
DESC sys.x$schema_flattened_keys;
Field	Type	Null	Key	Default	Extra
table_schema	varchar(64)	NO
table_name	varchar(64)	NO
index_name	varchar(64)	NO
non_unique	bigint(1)	YES		NULL
subpart_exists	bigint(1)	YES		NULL
index_columns	text	YES		NULL
SELECT * FROM sys.x$schema_flattened_keys;
CREATE DATABASE rkey;
CREATE TABLE rkey.rkey (
i INT,
j INT,
k INT,
PRIMARY KEY (i),
KEY (j),
KEY (j, k),
KEY (i, j, k)
);
SELECT * FROM sys.schema_redundant_indexes;
table_schema	table_name	redundant_index_name	redundant_index_columns	redundant_index_non_unique	dominant_index_name	dominant_index_columns	dominant_index_non_unique	subpart_exists	sql_drop_index
rkey	rkey	j	j	1	j_2	j,k	1	0	ALTER TABLE `rkey`.`rkey` DROP INDEX `j`
rkey	rkey	i	i,j,k	1	PRIMARY	i	0	0	ALTER TABLE `rkey`.`rkey` DROP INDEX `i`
DROP DATABASE rkey;
