config root man

drop table if exists t1;
create table t1 (`a` blob);
insert into t1 values("hello world"),("Hello mars"),(NULL);
select load_file(concat(@tmpdir,"/outfile-test.1"));
load_file(concat(@tmpdir,"/outfile-test.1"))
hello world
Hello mars
\N

select load_file(concat(@tmpdir,"/outfile-test.2"));
load_file(concat(@tmpdir,"/outfile-test.2"))
hello world
select load_file(concat(@tmpdir,"/outfile-test.3"));
load_file(concat(@tmpdir,"/outfile-test.3"))

ERROR HY000: File '../../tmp/outfile-test.1' already exists
ERROR HY000: File '../../tmp/outfile-test.2' already exists
ERROR HY000: File '../../tmp/outfile-test.3' already exists
select load_file(concat(@tmpdir,"/outfile-test.not-exist"));
load_file(concat(@tmpdir,"/outfile-test.not-exist"))
NULL
drop table t1;
select load_file(concat(@tmpdir,"/outfile-test.4"));
load_file(concat(@tmpdir,"/outfile-test.4"))
1

CREATE TABLE t1 (a INT);
EXPLAIN
SELECT *
INTO OUTFILE '/tmp/t1.txt'
  FIELDS TERMINATED BY ',' OPTIONALLY ENCLOSED BY '"' LINES TERMINATED BY '\r\n'
  FROM t1;
id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	filtered	Extra
1	SIMPLE	NULL	NULL	NULL	NULL	NULL	NULL	NULL	NULL	NULL	no matching row in const table
Warnings:
Note	1003	/* select#1 */ select NULL AS `a` from `test`.`t1`
DROP TABLE t1;
use test;
create table t1(a int);
select * into outfile "MYSQL_TEST_DIR/outfile-test1" from t1;
ERROR HY000: The MySQL server is running with the --secure-file-priv option so it cannot execute this statement
drop table t1;
create database mysqltest;
create user user_1@localhost;
grant all on mysqltest.* to user_1@localhost;
select schema_name
into outfile "../../tmp/outfile-test.4"
fields terminated by ',' optionally enclosed by '"'
 lines terminated by '\n'
from information_schema.schemata
where schema_name like 'mysqltest';
ERROR 28000: Access denied for user 'user_1'@'localhost' (using password: NO)
grant file on *.* to user_1@localhost;
select schema_name
into outfile "../../tmp/outfile-test.4"
fields terminated by ',' optionally enclosed by '"'
 lines terminated by '\n'
from information_schema.schemata
where schema_name like 'mysqltest';
use test;
revoke all privileges on *.* from user_1@localhost;
drop user user_1@localhost;
drop database mysqltest;