Get the max length allowed in column, mysql

Question

i need to know how to get the max size of an specific column in mysql, the table is

turno :

CREATE TABLE `turno` (  
`idTurno` tinyint(4) NOT NULL,  
`nombreTurno` varchar(20) COLLATE utf8_spanish2_ci NOT NULL,  
`horaInicio` tinyint(4) NOT NULL,  
`horafin` tinyint(4) NOT NULL,  
`valorTurno` int(11) NOT NULL,  
PRIMARY KEY (`idTurno`)) 
ENGINE=InnoDB DEFAULT CHARSET=utf8 COLLATE=utf8_spanish2_ci

the column :

`nombreTurno` varchar(20) COLLATE utf8_spanish2_ci NOT NULL

i should get :

im getting:

NULL

the query :

SELECT MAX( LENGTH( nombreTurno ) ) AS maxl
FROM turno

hope you can help me, thank you

no i dont have any record, the value that i need is about the table's structure. — user2132046, Mar 12 '13 at 17:10

John Woo · Accepted Answer · 2018-02-28T16:49:24.993

19

select COLUMN_NAME, CHARACTER_MAXIMUM_LENGTH 
from information_schema.columns
where table_schema = DATABASE() AND   -- name of your database
      table_name = 'turno' AND        -- name of your table
      COLUMN_NAME = 'nombreTurno'     -- name of the column

SQLFiddle Demo

edited Feb 28 '18 at 16:49

answered Mar 12 '13 at 17:16

John Woo

258,903
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498
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score 2 · Answer 2 · edited May 28 '21 at 07:37

2

The following SQL query will give the maximum column length.

SELECT max(length(column)) `max_column_length` from tab;

edited May 28 '21 at 07:37

StupidWolf

45,075
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answered Oct 02 '20 at 10:16

Adeel Raza Azeemi

571
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This only provides the maximum length of the longest record saved, not actually the maximum length the column is set to be capable of in the table setup. – Talk Nerdy To Me Oct 21 '21 at 21:34

Get the max length allowed in column, mysql

2 Answers2

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