MySQL database with unique fields ignored ending spaces

Question

My projects requires to start inputs from the user with the spacing on the left and spacing on the right of a word, for example \'apple\'. If the user types in \' apple\' or

Answer 1

Thanks to @kennethc. His answer works for me. Add a string length field to the table and to the unique key.

CREATE TABLE strings
( id bigint(20) unsigned NOT NULL AUTO_INCREMENT,
string varchar(255) COLLATE utf8_bin NOT NULL,
created_ts timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
string_length int(3),
PRIMARY KEY (id), UNIQUE KEY string (string,string_length) )
ENGINE=InnoDB AUTO_INCREMENT=1 DEFAULT CHARSET=utf8 COLLATE=utf8_bin

In MySQL it's possible to update the string length field with couple of triggers like this:

CREATE TRIGGER `string_length_insert` BEFORE INSERT ON `strings` FOR EACH ROW SET NEW.string_length = char_length(NEW.string);
CREATE TRIGGER `string_length_update` BEFORE UPDATE ON `strings` FOR EACH ROW SET NEW.string_length = char_length(NEW.string);