Max character length in text field

[Karl_T]

I would like to save very long string to a text field. My case is that I am saving canvas serialized data into text field for saving as state. However, the the text link cannot excceed certain length which is around 66535 something even though I set the field's max length as 0. What I can do to release the limit? Thanks.

[Sergio]

I think the textarea fields are configured as MediumText on the database, so you'll have to change that if your needs exceed its maximum length. 

Check this page for a reference (this is using InnoDB engine, BTW):

https://dev.mysql.com/doc/refman/5.7/en/storage-requirements.html#data-types-storage-reqs-strings

[Robin S]

Rather than edit the DB for an existing field, you could make a simple fieldtype module that extends FieldtypeTextarea:

<?php
class FieldtypeLongTextarea extends FieldtypeTextarea {

    /**
     * Module information
     */
    public static function getModuleInfo() {
        return array(
            'title' => 'Long Textarea',
            'version' => 1,
            'summary' => 'Field that stores multiple lines of text in a MySQL LONGTEXT column type.',
        );
    }

    /**
     * Get database schema used by the Field
     *
     * @param Field $field
     * @return array
     *
     */
    public function getDatabaseSchema(Field $field) {
        $schema = parent::getDatabaseSchema($field);
        $schema['data'] = 'longtext NOT NULL';
        $schema['keys']['data'] = 'FULLTEXT KEY data (data)';
        return $schema;
    }

}