Study Notes (11): mySQL database development tutorial - use a while loop in the function

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create function charn(ch varchar(20), n int)
return VARCHAR(255)
begin
declare result varchar(255);
declare i INT;
set result='';
set i=1;
while i<=n do
set result=CONCAT(result, ch, ' ')
set i=i+1;
end while;
return result;
end