修改数据库字符集:

ALTER DATABASE db_name DEFAULT CHARACTER SET character_name [COLLATE ...];

把表默认的字符集和所有字符列(CHAR,VARCHAR,TEXT)改为新的字符集:

ALTER TABLE tbl_name CONVERT TO CHARACTER SET character_name [COLLATE ...]
如:ALTER TABLE logtest CONVERT TO CHARACTER SET utf8 COLLATE utf8_general_ci;

只是修改表的默认字符集:

ALTER TABLE tbl_name DEFAULT CHARACTER SET character_name [COLLATE...];
如:ALTER TABLE logtest DEFAULT CHARACTER SET utf8 COLLATE utf8_general_ci;

修改字段的字符集:

ALTER TABLE tbl_name CHANGE c_name c_name CHARACTER SET character_name [COLLATE ...];
如:ALTER TABLE logtest CHANGE title title VARCHAR(100) CHARACTER SET utf8 COLLATE utf8_general_ci;

查看数据库编码:

show create database db_name;

查看表编码:

show create table tbl_name;

查看字段编码:

show full columns from tbl_name;

来源:http://www.diannaowa.com/index.php/archives/233