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--source include/have_innodb.inc
--source include/have_sequence.inc
# Each row is 1K.
create table t1 (
a varchar(255),
b varchar(255),
c varchar(255),
d varchar(255),
primary key(a,b,c,d)
) engine=innodb character set latin1;
# The data size is 16K * 1K = 16M
# 16M / (page_size=16K) = 1K pages.
SET unique_checks=0, foreign_key_checks= 0;
begin;
insert into t1 select
repeat(uuid(), 7),
repeat(uuid(), 7),
repeat(uuid(), 7),
repeat(uuid(), 7)
from seq_1_to_16384;
insert into t1 values ('z','z','z','z');
commit;
--echo # Restart the server to make sure we have an empty InnoDB Buffer Pool
--echo # (in the test's .opt file we've disabled buffer pool saving/loading
--echo # and also tried to disable any background activity)
SET GLOBAL innodb_fast_shutdown=0;
--source include/restart_mysqld.inc
set @innodb_pages_read0=
(select variable_value
from information_schema.session_status
where variable_name like 'innodb_pages_read');
let $analyze_output= `analyze format=json
select * from t1 force index (PRIMARY) order by a,b,c,d`;
evalp set @js='$analyze_output';
set @js=json_extract(@js, '$.query_block.nested_loop[0].table.r_engine_stats');
#select @js;
set @pages_accessed= cast(json_value(@js,'$.pages_accessed') as INT);
set @pages_read_count= cast(json_value(@js,'$.pages_read_count') as INT);
set @pages_prefetch_read_count= cast(json_value(@js,'$.pages_prefetch_read_count') as INT);
select @pages_accessed > 1000 and @pages_accessed < 1500;
set @total_read = (@pages_read_count + @pages_prefetch_read_count);
select @pages_accessed*0.75 < @total_read, @total_read < @pages_accessed*1.25;
set @innodb_pages_read1=
(select variable_value
from information_schema.session_status
where variable_name like 'innodb_pages_read');
set @innodb_pages_read_incr= (@innodb_pages_read1 - @innodb_pages_read0);
select @innodb_pages_read_incr > 1000, @innodb_pages_read_incr < 1500;
let $analyze_output= `analyze format=json
select * from t1 force index (PRIMARY) order by a,b,c,d`;
evalp set @js='$analyze_output';
set @js=json_extract(@js, '$.query_block.nested_loop[0].table.r_engine_stats');
--echo # This must just print pages_accessed. No page reads or prefetch reads,
--echo # because the previous query has read all the needed pages into the
--echo # buffer pool, which is set to be large enough to accomodate the whole
--echo # table.
--replace_regex /[0-9]+/NUMBER/
select @js;
set @pages_accessed2= cast(json_value(@js,'$.pages_accessed') as INT);
select @pages_accessed2 = @pages_accessed;
drop table t1;
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