mysql中select函数⽤法_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$] Where 出库⽇期 between #2005-1-4# and #2005-1-10# and 销售单价>100"
6、模糊条件:%表⽰任意多个字符,_(下划线)表⽰单个占位符
sql中select是什么意思'sql = "Select * from [sheet1$] 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 """",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 """",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,如果⼤家有任何疑问请给我留⾔,⼩编会及时回复⼤家的。在此也⾮常感谢⼤家对编程⼩技巧⽹站的⽀持!

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