1、C#窗体连接ACCESS数据库,实现包含查询/关键字查询的方法
string cxdm="";
DataSet ds1 = new DataSet();
DataTable dt1 = new DataTable();
ds1 = sql.ExecuteDataSet1("select gzdm from gzb where gznr like '%'+'" + cxkey.Text + "'+'%' ");
dt1 = ds1.Tables[0];
for (int k=0;k<dt1.Rows.Count;k++)
{
cxdm = cxdm + ","+dt1.Rows[k][0];
}
string str = "select * from gzjl where Instr('" + cxdm + "',gzdm)>0 order by id desc";
先从gzb表中找出满足搜索关键字的记录,然后并每一条记录的故障代码汇总成字符串,如(A02,A03,A04),然后再以该字符为搜索关键字,在另一个表gzjl中去查找被该字符串包含的记录。
2、C#窗体连接ACCESS数据库,实现时间段查询
string str = "select * from xljl where out_intime between '" + bdate + "' and '" + edate + "' order by id desc";
3、C#窗体连接ACCESS数据库,实现两个表连接查询
string str = "select gzjl.gzdc,gzjl.gzdm,gzb.gznr,gzjl.gzbt,gzjl.gzet from gzjl,gzb where gzjl.gzdm = gzb.gzdm ";
也可以改成如下:(join .. on ..方式)
string str = "select gzjl.gzdc,gzjl.gzdm,gzb.gznr,gzjl.gzbt,gzjl.gzet from gzjl inner join gzb on gzjl.gzdm = gzb.gzdm ";
4、C#窗体连接ACCESS数据库,实现字段为空的查询,以及存储系统时间
string str ="update gzjl set gzet='" + System.DateTime.Now + "' where gzdm='" + dm + "' and gzdc='A' and gzet is null ";