C# SqlClient按日期计数_C#_Sql_Sql Server

C# SqlClient按日期计数

c# sql sql-server

C# SqlClient按日期计数,c#,sql,sql-server,C#,Sql,Sql Server,我无法向谷歌表达我的问题，以了解如何做到这一点，我希望有人能帮助我这是我的出发点 SqlCommand command = new SqlCommand("SELECT BOOK_ID, BOOK_DATE, Sum(BOOK_COUNT) " + "FROM BOOKS " + "WHERE (BOOK_ID = '1' OR " +

我无法向谷歌表达我的问题，以了解如何做到这一点，我希望有人能帮助我

这是我的出发点

SqlCommand command = new SqlCommand("SELECT BOOK_ID, BOOK_DATE, Sum(BOOK_COUNT) " +
                                    "FROM BOOKS " +
                                    "WHERE (BOOK_ID = '1' OR " +
                                           "BOOK_ID = '2' OR " +
                                           "BOOK_ID = '3' )  " +
                                    "AND STATUS  = '0'    " +
                                    "GROUP BY BOOK_ID, BOOK_DATE ", cn);

SqlDataReader reader = command.ExecuteReader();

while (reader.Read())
{
    int id = (int)reader[0]; 
    DateTime date = (DateTime)reader[1]; 
    int count = (int)reader[2];

    if (id == 1)
    {
       /*...*/
    }

    if (id == 2)
    {
       /*...*/
    }

    if (id == 3)
    {
       /*...*/
    }
 }

 reader.Close();

DBSCA

我想排序的日期，如果日期和id是相同的，那么得到的书籍计数。。。像这样：

BOOK_DATE  BOOK_ID  BOOK_COUNT  
2014.11.17     1        1         
2014.11.21     2        1           
2014.11.25     2        2           
2014.11.26     1        2           
2014.11.26     3        2           
2014.11.27     3        1           
2014.11.28     3        1

如果有人能帮我，谢谢，我为英语不好道歉

ORDER BY DATEADD(DAY, 0, DATEDIFF(DAY, 0, BOOK_DATE)), Sum(BOOK_COUNT)

DATEADD（dd，0，DATEDIFF（DAY，0，BOOK_DATE））只获取记录的日期部分。您还需要使用此功能进行分组

由于@marc_s的建议而编辑

DATEADD（dd，0，DATEDIFF（DAY，0，BOOK_DATE））只获取记录的日期部分。您还需要使用此功能进行分组

由于@marc_s的建议而编辑

DATEADD（dd，0，DATEDIFF（DAY，0，BOOK_DATE））只获取记录的日期部分。您还需要使用此功能进行分组

由于@marc_s的建议而编辑

DATEADD（dd，0，DATEDIFF（DAY，0，BOOK_DATE））只获取记录的日期部分。您还需要使用此功能进行分组

由于@marc_s

建议按结果集中的第二个值排序而编辑，只需添加

按2排序

SqlCommand command = new SqlCommand("SELECT BOOK_ID, BOOK_DATE, Sum(BOOK_COUNT) " +
                                    "FROM BOOKS " +
                                    "WHERE (BOOK_ID = '1' OR " +
                                           "BOOK_ID = '2' OR " +
                                           "BOOK_ID = '3' )  " +
                                    "AND STATUS  = '0'    " +
                                    "GROUP BY BOOK_ID, BOOK_DATE 
ORDER BY 2", cn);

要按结果集中的第二个值排序，只需添加

orderby2

SqlCommand command = new SqlCommand("SELECT BOOK_ID, BOOK_DATE, Sum(BOOK_COUNT) " +
                                    "FROM BOOKS " +
                                    "WHERE (BOOK_ID = '1' OR " +
                                           "BOOK_ID = '2' OR " +
                                           "BOOK_ID = '3' )  " +
                                    "AND STATUS  = '0'    " +
                                    "GROUP BY BOOK_ID, BOOK_DATE 
ORDER BY 2", cn);

要按结果集中的第二个值排序，只需添加

orderby2

SqlCommand command = new SqlCommand("SELECT BOOK_ID, BOOK_DATE, Sum(BOOK_COUNT) " +
                                    "FROM BOOKS " +
                                    "WHERE (BOOK_ID = '1' OR " +
                                           "BOOK_ID = '2' OR " +
                                           "BOOK_ID = '3' )  " +
                                    "AND STATUS  = '0'    " +
                                    "GROUP BY BOOK_ID, BOOK_DATE 
ORDER BY 2", cn);

要按结果集中的第二个值排序，只需添加

orderby2

SqlCommand command = new SqlCommand("SELECT BOOK_ID, BOOK_DATE, Sum(BOOK_COUNT) " +
                                    "FROM BOOKS " +
                                    "WHERE (BOOK_ID = '1' OR " +
                                           "BOOK_ID = '2' OR " +
                                           "BOOK_ID = '3' )  " +
                                    "AND STATUS  = '0'    " +
                                    "GROUP BY BOOK_ID, BOOK_DATE 
ORDER BY 2", cn);

这个<编码>将<编码>图书日期转换为<编码>日期，然后在

分组中使用它
SELECT BOOK_ID,
       CONVERT(DATE, BOOK_DATE),
       Sum(BOOK_COUNT)
FROM   BOOKS
WHERE   BOOK_ID IN (1,2,3)
       AND STATUS = 0
GROUP  BY BOOK_ID,
          CONVERT(DATE, BOOK_DATE) 

这个<编码>将<编码>图书日期

转换为<编码>日期，然后在

分组中使用它
SELECT BOOK_ID,
       CONVERT(DATE, BOOK_DATE),
       Sum(BOOK_COUNT)
FROM   BOOKS
WHERE   BOOK_ID IN (1,2,3)
       AND STATUS = 0
GROUP  BY BOOK_ID,
          CONVERT(DATE, BOOK_DATE) 

这个<编码>将<编码>图书日期

转换为<编码>日期，然后在

分组中使用它
SELECT BOOK_ID,
       CONVERT(DATE, BOOK_DATE),
       Sum(BOOK_COUNT)
FROM   BOOKS
WHERE   BOOK_ID IN (1,2,3)
       AND STATUS = 0
GROUP  BY BOOK_ID,
          CONVERT(DATE, BOOK_DATE) 

这个<编码>将<编码>图书日期

转换为<编码>日期，然后在

分组中使用它
SELECT BOOK_ID,
       CONVERT(DATE, BOOK_DATE),
       Sum(BOOK_COUNT)
FROM   BOOKS
WHERE   BOOK_ID IN (1,2,3)
       AND STATUS = 0
GROUP  BY BOOK_ID,
          CONVERT(DATE, BOOK_DATE) 

分组依据
日期时间字段的日期部分：
SqlCommand command = new SqlCommand("SELECT BOOK_ID, DATEADD(DAY, 0, DATEDIFF(DAY, 0, BOOK_DATE)), Sum(BOOK_COUNT) " +
                                    "FROM BOOKS " +
                                    "WHERE (BOOK_ID = '1' OR " +
                                           "BOOK_ID = '2' OR " +
                                           "BOOK_ID = '3' )  " +
                                    "AND STATUS  = '0'    " +
                                    "GROUP BY BOOK_ID, DATEADD(DAY, 0, DATEDIFF(DAY, 0, BOOK_DATE)) 
ORDER BY 2", cn);

分组依据
日期时间字段的日期部分：
SqlCommand command = new SqlCommand("SELECT BOOK_ID, DATEADD(DAY, 0, DATEDIFF(DAY, 0, BOOK_DATE)), Sum(BOOK_COUNT) " +
                                    "FROM BOOKS " +
                                    "WHERE (BOOK_ID = '1' OR " +
                                           "BOOK_ID = '2' OR " +
                                           "BOOK_ID = '3' )  " +
                                    "AND STATUS  = '0'    " +
                                    "GROUP BY BOOK_ID, DATEADD(DAY, 0, DATEDIFF(DAY, 0, BOOK_DATE)) 
ORDER BY 2", cn);

分组依据
日期时间字段的日期部分：
SqlCommand command = new SqlCommand("SELECT BOOK_ID, DATEADD(DAY, 0, DATEDIFF(DAY, 0, BOOK_DATE)), Sum(BOOK_COUNT) " +
                                    "FROM BOOKS " +
                                    "WHERE (BOOK_ID = '1' OR " +
                                           "BOOK_ID = '2' OR " +
                                           "BOOK_ID = '3' )  " +
                                    "AND STATUS  = '0'    " +
                                    "GROUP BY BOOK_ID, DATEADD(DAY, 0, DATEDIFF(DAY, 0, BOOK_DATE)) 
ORDER BY 2", cn);

分组依据
日期时间字段的日期部分：
SqlCommand command = new SqlCommand("SELECT BOOK_ID, DATEADD(DAY, 0, DATEDIFF(DAY, 0, BOOK_DATE)), Sum(BOOK_COUNT) " +
                                    "FROM BOOKS " +
                                    "WHERE (BOOK_ID = '1' OR " +
                                           "BOOK_ID = '2' OR " +
                                           "BOOK_ID = '3' )  " +
                                    "AND STATUS  = '0'    " +
                                    "GROUP BY BOOK_ID, DATEADD(DAY, 0, DATEDIFF(DAY, 0, BOOK_DATE)) 
ORDER BY 2", cn);

仅供参考（1,2,3）

如果

图书ID

是一个数字数据类型（应该是！），那么您不应该在

其中条款中添加不必要的单引号（应该是！），那么您不应该在WHERE
clauseFYI较短的符号WHERE BOOK_ID in（1,2,3）…中添加不必要的单引号。
如果BOOK_ID
是数字数据类型（应该是！），则不应在WHERE
clauseFYI较短符号WHERE BOOK\u ID in（1,2,3）…中添加不必要的单引号。
如果BOOK\u ID
是数字数据类型（应该是！），那么您不应该在中添加不必要的单引号，因为在中，
子句我更喜欢使用日期添加中的日期
指示器-它比dd
明显得多，也更清晰……（这使它更易于维护！）我更喜欢使用DATEADD
中的DAY
指示器-它比dd
更明显、更清晰……（这使它更易于维护！）我更喜欢使用DATEADD
中的DAY
指示器-它比dd
更明显、更清晰……（这使它更易于维护！）我更喜欢使用DATEADD
中的DAY
指示器-它比dd
更明显、更清晰……（这使它更易于维护！）我更喜欢使用DATEADD
中的DAY
指示器-它比dd
更明显、更清晰……（这使它更易于维护！）我更喜欢使用DATEADD
中的DAY
指示器-它比dd
更明显、更清晰……（这使它更易于维护！）我更喜欢使用DATEADD
中的DAY
指示器-它比dd
更明显、更清晰……（这使它更易于维护！）我更喜欢使用日期添加中的日期
指示器-它比dd
更明显、更清晰（这使它更易于维护！）假设？BOOK_ID`是数字的（或应该是数字的），我会避免在WHERE
子句中添加不必要的单引号…假设？BOOK\u ID`是数字的（或应该是），我会避免在WHERE
子句中添加不必要的单引号…假设？BOOK\u ID`是数字的（或应该是），我会避免在WHERE
子句中添加不必要的单引号…假设？BOOK_ID`是数字（或应该是数字），我会避免在WHERE
子句中添加不必要的单引号。。。