（项目积累的）SQL数据库点滴

最近的的系统用的数据库是mssql，软件mssql 2008 r2

1、存储过程：后勤的综合管理系统(后端内网访问)三层架构配套用的是存储过程，里面列表展示的都是用存储过程，如下：

1）数据库脚本

USE [ProjectDB]
GO
/****** Object:  StoredProcedure [dbo].[UP_NetworkBugInfo_List_select]    Script Date: 09/18/2016 21:44:33 ******/
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO  
-- =============================================
-- Author:类菌体
-- Create date: 2014-06-09
-- Description:    分页查询信息
-- =============================================
ALTER procedure [dbo].[UP_NetworkBugInfo_List_select]
@StartIndex int=1,--分页开始序号
@EndIndex int=10,--分页结束序号
@WhereSql nvarchar(2000)='',--分页查询条件
@RecordCount int=0 output --当前条件下的总记录数
as
begin
declare @sql nvarchar(max)
declare @total int

set @sql='select @n=count(1) from NetworkBugInfo a   where 1=1 '+@WhereSql
exec sp_executesql @sql, N'@n int output',@total output --@sql相当于procedure主体，N'@n int'相当于参数部分，相当于procedure调用

set @RecordCount=@total

set @sql='select * from
            (select row_number() over(order by t1.NetworkBugId desc) as Row, t1.NetworkBugId,t1.InternetNumber,t1.Username,t1.BugType,t1.PhoneNumber,t1.ShortNumber,t1.Campus,t1.Building,t1.Room,t1.BugDetail,t1.SubmitTime,t1.State,t1.OnePrincipal,t1.SubmitIp,t1.OrderTimes,t1.UserNames,t1.bxfs from NetworkBugInfo t1
            where 1=1 '+@WhereSql+'  ) a where Row between '+convert(varchar(100), @StartIndex)+' and '+convert(varchar(100), @EndIndex) 
exec(@sql) 
end

2）、主要操作数据库的方法

 /// <summary>
        /// 根据条件分页查询信息
        /// </summary>
        /// <param name="pageIndex">当前页码</param>
        /// <param name="pageSize">每页大小</param>
        /// <param name="whereSql">分页查询条件</param>
        /// <param name="recordCount">out参数，当前条件下的总记录数</param>
        /// <returns>分页查询后的信息</returns>
        public DataTable GetList(int pageIndex, int pageSize, string whereSql, out int recordCount)
        {
            DataTable dt = null;
            int startIndex = pageIndex <= 1 ? 1 : ((pageIndex - 1) * pageSize + 1);
            int endIndex = startIndex + pageSize - 1;
            SqlParameter[] parms = { 
                                       new SqlParameter("@StartIndex",SqlDbType.Int),
                                       new SqlParameter("@EndIndex",SqlDbType.Int),
                                       new SqlParameter("@WhereSql",SqlDbType.NVarChar,2000),
                                       new SqlParameter("@RecordCount",SqlDbType.Int)
                                   };
            parms[0].Value = startIndex;
            parms[1].Value = endIndex;
            parms[2].Value = whereSql;
            parms[3].Direction = ParameterDirection.Output;
            dt = SQLHelper.GetDataTable(CommandType.StoredProcedure, "UP_NetworkBugInfo_List_select", parms);
            recordCount = Convert.ToInt32(parms[3].Value);
            return dt;
        }

 2、随机查询：有时候需要随机选出一些数据。比如有一个后期回访的活动，需要随机抽取某些客户的数据    

order by newid()

select TOP 10 * from lybug where State=' 完成处理' order by   newid() ---含义代表随机抽取10条记录

3、查询插入：主要使用比如一般从excel导入ｍｓｓｑｌ都会直接导入形成一个表，导入方法可以使用ｍｓｓｑｌ２００８ｒ２，导进去记得转换下数据类型形成一个表对象以后，可以直接选择该对象的字段插入到目标表记录中

同步就业基地
insert into tb_sx_jdinfo(_mc,_jgm,_xxdz,_lxdh,_dwjj,_kfr,kfdw,jyjiid,sfzy,Cxqhzdq,compTypeID,compTradeID) select  b.compName,b.OrganizationCode,b.compAdress,b.compContactTel,b.compRemark,b.userCode,b.kfdw,b.compID,1,b.compCityID,b.compTypeID,b.compTradeID
from compJobState as t join newCompBasic as b on t.CompID=b.compID join newCompJob as j on t.jobID=j.jobID
where t.CountYear='2016' and b.IsBasic='1'

４、微软sql server 尽量使用sqlserver 2008r2版本,备份，导出数据等可以选择知导出结构，导出数据，导出结构和数据，在查询窗体下查询结果可以选择复制（带表头）

5、查询重复，删除重复 (只保留一条)

select * from tb_sx_jdinfo where _mc in (select   _mc from   tb_sx_jdinfo group by   _mc having count(_mc) > 1)

delete from tb_sx_jdinfo where _mc in (select   _mc from tb_sx_jdinfo group by   _mc   having count (_mc) > 1) and _dm not in (select min(_dm) from   tb_sx_jdinfo group by _mc having count(_mc)>1)

 6、查询账户不为空

select loginid as 工号,lastname as  姓名 from HrmResource  where  isnull(loginid,'')<>''