MySQL之补充

查询时去掉重复值

SELECT DISTINCT(s_name) FROM students

  分组后的条件查询

SELECT * FROM students GROUP BY s_id HAVING s_id >5

having  为分组后的判断条件

MySQL中的奇数与偶数

奇数   num%2=1

SELECT * FROM students 
WHERE s_id%2=1

偶数  num%2=0

SELECT * FROM students 
WHERE s_id%2=0