max(length(field)) in mysql
If I say:
select max(length(Name))
from my_table
I get the result as 18, but I want the concerned data also. So if I say:
select max(length(Name)),
Name
from my_table
...it does not work. There should be a self join I guess which I am unable to figure it out.
Can anyo开发者_C百科ne please provide me a clue?
SELECT name, LENGTH(name) AS mlen
FROM mytable
ORDER BY
mlen DESC
LIMIT 1
Edited, will work for unknown max() values:
select name, length( name )
from my_table
where length( name ) = ( select max( length( name ) ) from my_table );
Ok, I am not sure what are you using(MySQL, SLQ Server, Oracle, MS Access..) But you can try the code below. It work in W3School example DB. Here try this:
SELECT city, max(length(city)) FROM Customers;
In case you need both max and min from same table:
select * from (
(select city, length(city) as maxlen from station
order by maxlen desc limit 1)
union
(select city, length(city) as minlen from station
order by minlen,city limit 1))a;
Use:
SELECT mt.name
FROM MY_TABLE mt
GROUP BY mt.name
HAVING MAX(LENGTH(mt.name)) = 18
...assuming you know the length beforehand. If you don't, use:
SELECT mt.name
FROM MY_TABLE mt
JOIN (SELECT MAX(LENGTH(x.name) AS max_length
FROM MY_TABLE x) y ON y.max_length = LENGTH(mt.name)
Select URColumnName From URTableName Where length(URColumnName ) IN
(Select max(length(URColumnName)) From URTableName);
This will give you the records in that particular column which has the maximum length.
Use CHAR_LENGTH() instead-of LENGTH() as suggested in: MySQL - length() vs char_length()
SELECT name, CHAR_LENGTH(name) AS mlen FROM mytable ORDER BY mlen DESC LIMIT 1
select *
from my_table
where length( Name ) = (
select max( length( Name ) )
from my_table
limit 1
);
It this involves two table scans, and so might not be very fast !
I suppose you could use a solution such as this one :
select name, length(name)
from users
where id = (
select id
from users
order by length(name) desc
limit 1
);
Might not be the optimal solution, though... But seems to work.
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