MySql数据库中Select用法小结

一、条件筛选

1、数字筛选：sql = "select * from [sheet1$] where 销售单价 > 100"

2、字符条件：sql = "select * from [sheet1$] where 物品名称 ='挡泥板'"

3、日期条件：sql = "select * from [sheet1$] where 物品名称 ='挡泥板'"

4、区间条件：sql = "select * from [sheet1$] where 出库日期 between #2005-1-4# and #2005-1-10#"

5、多个条件：用and,or连接

'sql = "select * from [sheet1$] where 出库日期 between #2005-1-4# and #2005-1-10# and 销售单价>100"

6、模糊条件：%表示任意多个字符,_(下划线)表示单个占位符

'sql = "select * from [sheet1$] where 物品名称 like '%扶手%'"

7、插入变量查询:

'sr = "挡泥板"
'sql = "select * from [sheet1$] where 物品名称 ='" & sr & "'"

8、在字符串组里：

'sql = "select * from [sheet1$] where 物品名称 in('车衣','扶手箱')"

9、借用函数优化：

'sql = "select * from [sheet1$] where left(物品代码,3)='028'"

二、指定筛选

1、筛选全部字段:*表示全部字段

'sql = "select * from chuku"

2、筛选指定字段：在from前面列出要显示的所有字段,如果要跳过的用""""

'sql = "select """",出库日期,"""",物品代码,"""",规格,单位 from chuku"

3、筛选不重复的：distinct 字段名 筛选不重复的记录

'sql = "select distinct """",物品代码 from chuku"

4、按百分比筛选:top n percent 可以显示前百分之n的记录

'sql = "select top 30 percent * from chuku"

'对筛选的字段用函数进行进一步的处理和格式化

'sql = "select id,format(出库日期,""yyyy-mm-dd"") from chuku"

5、排序:desc降序,asc升序

'sql = "select * from chuku order by 出库日期 asc,销售单价 desc"
'sql = "select top 10 * from chuku order by 出库日期 asc,销售单价 desc" '筛选销售数量前10()

三、分组显示

group by 可以配合函数进行分组求和,分组求最大值等。

'sql = "select """","""",物品代码,"""","""","""",sum(出库数量) from chuku group by 物品代码" ' 跳过的用""""

按条件显示分组记录

'sql = "select """","""",物品代码,"""","""","""",sum(出库数量) from chuku group by 物品代码 having sum(出库数量)>=3"

以上所述是小编给大家介绍的mysql数据库中select用法小结，希望对大家有所帮助