选择某表的某列从某表
select tablesname.column from tables;
挑选某表的某列于从某库的某表
select tablesname.column from database.tables
挑选某表从某列于按照某列于的顺序
select column from database order by column;
挑选多列从某表按照某两列排序
select column1,column2,c3 from database order by column1,column2;
挑选多列从某表中按照某列于降序排序
select column1,column2,c3 from database order by column1 desc;
挑选多列从某表按照某列于降序排序后再按照某列于顺序排序
select column1,column2,c3 from database order by column1 desc,column2;
查询某行从某表某行排序挑最值
select column from tables order by column1 desc limit 1;