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|
--source include/big_test.inc
--source include/have_sequence.inc
--source include/have_64bit.inc
set @save_rand_seed1= @@RAND_SEED1;
set @save_rand_seed2= @@RAND_SEED2;
set @@RAND_SEED1=810763568, @@RAND_SEED2=600681772;
create table t1(a int);
insert into t1 select seq from seq_1_to_10000 order by rand(),seq;
delimiter |;
--echo #
--echo # parameters:
--echo # mean mean for the column to be considered
--echo # max_val max_value for the column to be considered
--echo #
--echo # This function generate a sample of a normal distribution
--echo # This function return a point
--echo # of the normal distribution with a given mean.
--echo #
CREATE FUNCTION
generate_normal_distribution_sample(mean DOUBLE, max_val DOUBLE)RETURNS DOUBLE
BEGIN
DECLARE z DOUBLE DEFAULT 0;
SET z= (rand() + rand() + rand() + rand() + rand() + rand())/6;
SET z= 2*(max_val-mean)*z;
SET z= z + mean - (max_val-mean);
return z;
END|
--echo #
--echo # parameters:
--echo # len length of the random string to be generated
--echo #
--echo # This function generates a random string for the length passed
--echo # as an argument with characters in the range of [A,Z]
--echo #
CREATE FUNCTION generate_random_string(len INT) RETURNS varchar(128)
BEGIN
DECLARE str VARCHAR(256) DEFAULT '';
DECLARE x INT DEFAULT 0;
WHILE (len > 0) DO
SET x =round(rand()*25);
SET str= CONCAT(str, CHAR(65 + x));
SET len= len-1;
END WHILE;
RETURN str;
END|
--echo #
--echo # parameters:
--echo # mean mean for the column to be considered
--echo # min_val min_value for the column to be considered
--echo # max_val max_value for the column to be considered
--echo #
--echo # This function generate a normal distribution sample in the range of
--echo # [min_val, max_val]
--echo #
CREATE FUNCTION
clipped_normal_distribution(mean DOUBLE, min_val DOUBLE, max_val DOUBLE)
RETURNS INT
BEGIN
DECLARE r DOUBLE DEFAULT 0;
WHILE 1=1 DO
set r= generate_normal_distribution_sample(mean, max_val);
IF (r >= min_val AND r <= max_val) THEN
RETURN round(r);
end if;
END WHILE;
RETURN 0;
END|
delimiter ;|
create table t2 (id INT NOT NULL, a INT, b int);
insert into t2
select a, clipped_normal_distribution(12, 0, 64),
clipped_normal_distribution(32, 0, 128)
from t1;
CREATE TABLE t3(
id INT NOT NULL,
names VARCHAR(64),
address VARCHAR(128),
PRIMARY KEY (id)
);
--echo #
--echo # table t3 stores random strings calculated from the length stored in
--echo # table t2
--echo #
insert into t3
select id, generate_random_string(a), generate_random_string(b) from t2;
let $query= select id DIV 100 as x,
MD5(group_concat(substring(names,1,3), substring(address,1,3)
order by id))
FROM t3
GROUP BY x;
--echo #
--echo # All records fit in memory
--echo #
set sort_buffer_size=262144*10;
--source include/analyze-format.inc
eval analyze format=json $query;
flush status;
eval $query;
show status like '%sort%';
set sort_buffer_size=default;
--echo #
--echo # Test for merge_many_buff
--echo #
set sort_buffer_size=32768;
--source include/analyze-format.inc
eval analyze format=json $query;
flush status;
eval $query;
show status like '%sort%';
set sort_buffer_size=default;
set @@RAND_SEED1= @save_rand_seed1;
set @@RAND_SEED2= @save_rand_seed2;
drop function generate_normal_distribution_sample;
drop function generate_random_string;
drop function clipped_normal_distribution;
drop table t1, t2, t3;
|
