I have a table “t_user”, it’s character set is “latin1” when create it, and I want to save some unicode text at field “username”, but when I saved, the data is “????”, so I need to change character set from “latin1” to “utf8”.
ALTER TABLE `t_user` CHARSET=utf8;
then I saved unicode data again, but still “????”.
I found that the character set of the field “username” is still “latin1”, so I droped field “username”,
ALTER TABLE `t_user` DROP COLUMN `username`;
and then create it again,
ALTER TABLE `t_user` ADD COLUMN `username` VARCHAR(20) NULL;
the character set of the field “username” is “utf8” now, and the unicode data was saved correctly.
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