使用DISTINCT关键字
SELECT DISTINCT column_name FROM table_name;
使用GROUP BY子句SELECT column_name FROM table_name GROUP BY column_name;
使用子查询SELECT column_name FROM table_name WHERE column_name IN (SELECT DISTINCT column_name FROM table_name);
使用HAVING子句SELECT column_name FROM table_name GROUP BY column_name HAVING COUNT(column_name) = 1;
使用临时表CREATE TEMPORARY TABLE temp_table ASSELECT DISTINCT column_name FROM table_name;SELECT * FROM temp_table;
