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# Create the old-version of the table
call mtr.add_suppression(".*Incorrect definition of table mysql.column_stats:.*");
alter table mysql.column_stats rename test.t1;
CREATE TABLE mysql.column_stats (
`db_name` varchar(64) COLLATE utf8mb3_bin NOT NULL,
`table_name` varchar(64) COLLATE utf8mb3_bin NOT NULL,
`column_name` varchar(64) COLLATE utf8mb3_bin NOT NULL,
`min_value` varbinary(255) DEFAULT NULL,
`max_value` varbinary(255) DEFAULT NULL,
`nulls_ratio` decimal(12,4) DEFAULT NULL,
`avg_length` decimal(12,4) DEFAULT NULL,
`avg_frequency` decimal(12,4) DEFAULT NULL,
`hist_size` tinyint(3) unsigned DEFAULT NULL,
`hist_type` enum('SINGLE_PREC_HB','DOUBLE_PREC_HB') COLLATE utf8mb3_bin DEFAULT NULL,
`histogram` varbinary(255) DEFAULT NULL,
PRIMARY KEY (`db_name`,`table_name`,`column_name`)
) ENGINE=Aria DEFAULT CHARSET=utf8mb3 COLLATE=utf8mb3_bin PAGE_CHECKSUM=1 TRANSACTIONAL=0 COMMENT='Statistics on Columns';
create table t0(a int);
insert into t0 values (0),(1),(2),(3),(4),(5),(6),(7),(8),(9);
INSERT INTO mysql.column_stats VALUES
('test','t0','a','0','9',0.0000,4.0000,1.0000,5,'DOUBLE_PREC_HB', x'5555AAAA00');
flush tables;
analyze select * from t0 where a<3;
id select_type table type possible_keys key key_len ref rows r_rows filtered r_filtered Extra
1 SIMPLE t0 ALL NULL NULL NULL NULL 10 10.00 100.00 30.00 Using where
# restart
select hex(histogram) from mysql.column_stats where table_name='t0' and db_name='test';
hex(histogram)
5555AAAA00
analyze select * from t0 where a<3;
id select_type table type possible_keys key key_len ref rows r_rows filtered r_filtered Extra
1 SIMPLE t0 ALL NULL NULL NULL NULL 10 10.00 100.00 30.00 Using where
create table t2 (a int);
# This currently just pretends that the histogram was collected.
analyze table t2 persistent for all;
Table Op Msg_type Msg_text
test.t2 analyze status Engine-independent statistics collected
test.t2 analyze status Table is already up to date
select * from mysql.column_stats where table_name='t2' and db_name='test';
db_name table_name column_name min_value max_value nulls_ratio avg_length avg_frequency hist_size hist_type histogram
analyze select * from t0 where a<3;
id select_type table type possible_keys key key_len ref rows r_rows filtered r_filtered Extra
1 SIMPLE t0 ALL NULL NULL NULL NULL 10 10.00 33.33 30.00 Using where
drop table t0, t1, t2;
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