Is there any way to display the size of the string in a MYSQL result?

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Is there any way to display the string size in a MYSQL result?

I need, for example, to know the size of a given string returned in a SELECT with group_concat.

What I want would be more or less like this example:

SELECT "nome", FUNCAO_PARA_OBTER_TAMANHO("nome")

I’d like to return something like:

 nome | 4
mysql

3 answers

9


To know the number of characters you can use char_lenght() in the example returns 4 because the return is based on the characters and not on the bytes as it does lenght() that returns 6(number of bytes);

select CHAR_LENGTH("ação")

select LENGTH("ação")

Example - sqlfiddle

  • Interesting. It seems that it is more convenient because of the UTF-8 and the like!

5

I don’t know if that’s what you’re looking for

SELECT nome, LENGTH(nome) as tamanho FROM ....

5

It depends on which measure you want to get.

There are the functions LENGTH() and CHAR_LENGTH().

The function LENGTH() calculate the measure in bytes.

The function CHAR_LENGTH() calculates the measure in characters.

Somewhat coarse comparison with PHP, LENGTH() is equivalent tostrlen() and CHAR_LENGTH() is equivalent to mb_strlen().

An interesting curiosity, both functions allow to make a cast of the parameter, setting the type of charset.

select length(_utf8 '言葉'), char_length(_utf8 '言葉')

select length(_utf8 'ação'), char_length(_utf8 'ação')

  • Thanks for the explanation. Spared me from asking a question. When I did LENGTH('é') returned 2. Should return 1. But with the CHAR_LENGTH was just right.

  • 2

    length() returns the actual size in bytes, which is very different from the number of characters. I think it’s best not to talk too much about bytes or else the kib guy, Mib, Gib.. rsrsrssr

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