mysql: how to outfile csv - limit x number of rows? - mysql

Question

I have some queries like this
(SELECT 'title', 'created_at', 'modified_at')
UNION
(select title, created_at, modified_at from table1 order by created_at
INTO OUTFILE 'result.csv'
CHARACTER SET utf8
FIELDS TERMINATED BY ',' OPTIONALLY ENCLOSED BY '"' ESCAPED BY '"' LINES TERMINATED BY '\r\n');
and the the result is more than 10000 rows.
Is there a way to split this into multiple files?
I would like to limit the number of rows.
I know that I can do something like this:
select * from table1 limit 0, 1000 into outfile result1.csv
select * from table1 limit 1000, 1000 into outfile result2.csv
select * from table1 limit 2000, 1000 into outfile result3.csv
...
since there's more than 10000 rows, I am wondering if I can use some kind of loop.
Any advice and help will be greatly appreciated!
::EDIT::
I wrote repeat procedure but it gives me a syntax error.
DELIMITER ;;
CREATE PROCEDURE `reapeatloop`()
BEGIN
declare x int;
declare filename varchar(255);
declare lowlimit int;
SET x = 0;
REPEAT
set lowlimit = x*1000;
(select * from table1 limit lowlimit, 1000
INTO OUTFILE concat('post',x,'.csv')
CHARACTER SET utf8
FIELDS TERMINATED BY ',' ENCLOSED BY '"' ESCAPED BY '"' LINES
TERMINATED BY '\r\n');
SET x = x + 1;
UNTIL x > 19 END REPEAT;
END;;
DELIMITER ;
Inside this query, I used local variable to define csv and limit value and this gives syntax error. can anyone see what's wrong with this query?
as soon as I change this variable to some number, or string, it creates procedure successfully.

Answer 1

You have some mistake in your procedure. Specially check the SELECT INTO OUTFILE.
Be careful about the position of FROM.
In your case try this:
DROP PROCEDURE reapeatloop;
DELIMITER $$
CREATE PROCEDURE `reapeatloop`()
BEGIN
declare x int;
declare filename varchar(255);
declare lowlimit int;
SET x = 0;
REPEAT
set lowlimit = x*1000;
SET #fullOutputPath := CONCAT('"D:/post',x,'.csv"');
set #q1 := concat("select * INTO OUTFILE ", #fullOutputPath,
" CHARACTER SET utf8 FIELDS TERMINATED BY ',' ENCLOSED BY '\"' ESCAPED BY '\"' LINES TERMINATED BY '\r\n'
from table1 limit ", lowlimit, ",1000");
select #q1;
prepare s1 from #q1;
execute s1;deallocate prepare s1;
SET x = x + 1;
UNTIL x > 19 END REPEAT;
END$$
DELIMITER ;