Query中的Sql语句 |
答題得分者是:peterpcc
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小丫123
初階會員 發表:85 回覆:62 積分:29 註冊:2004-08-31 發送簡訊給我 |
我用的数据库是MYSQL,建立了表t_xsb(学生基本信息表),td_xbdm(系别),td_zydm(专业)
我想通过Sql语句将这几个表连接,t_xsb(xh(*),xm,xbdm,zydm),
td_xbdm(xbdm(*),xbmc),td_zydm(zydm(*),zymc),通过xmedit来检索相关信息。
我自己编了好多次,结果都有错。恳请前辈指点!!
var xm,sqlstr:string; begin xm:=trim(edit1.Text ); if length(xm)<1 then begin sqlstr:='select t_xsb.xm as xm,t_xsb.csny as csny,td_zydm.zymc as zymc,td_xbdm.xbmc from t_xsb '; sqlstr:=sqlstr ' inner join td_zydm on t_xsb.zydm=td_zydm.zydm'; sqlstr:=sqlstr ' inner join td_xbdm on t_xsb.xbdm=td_xbdm.xbdm'; end else begin xm:='%' xm '%'; sqlstr:='select t_xsb.xm as xm,t_xsb.csny as csny,td_zydm.zymc as zymc,td_xbdm.xbmc from t_xsb '; sqlstr:=sqlstr ' inner join td_zydm on t_xsb.zydm=td_zydm.zydm'; sqlstr:=sqlstr ' inner join td_xbdm on t_xsb.xbdm=td_xbdm.xbdm'; sqlstr:=sqlstr 'where(t_xsb.xm like ''' xm ''')'; end; query1.Close; query1.SQL.Clear ; query1.SQL.Add(sqlstr); query1.Open; end;發表人 - 小丫123 於 2004/12/06 16:42:52 發表人 - 小丫123 於 2004/12/06 17:05:34 |
peterpcc
一般會員 發表:6 回覆:37 積分:13 註冊:2004-09-27 發送簡訊給我 |
試試這樣,應該是可以的.
var
xm,sqlstr:string;
begin
xm:=trim(edit1.Text );
sqlstr:='select t_xsb.xm as xm,t_xsb.csny as csny,td_zydm.zymc as zymc,td_xbdm.xbmc from t_xsb ';
sqlstr:=sqlstr ' inner join td_zydm on t_xsb.zydm=td_zydm.zydm';
sqlstr:=sqlstr ' inner join td_xbdm on t_xsb.xbdm=td_xbdm.xbdm';
if xm<>'' then
begin
xm:='%' xm '%';
sqlstr:=sqlstr ' where t_xsb.xm like ''' xm ''' ';
end;
query1.Close;
query1.SQL.Clear ;
query1.SQL.Add(sqlstr);
query1.Open; end;
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peterpcc
一般會員 發表:6 回覆:37 積分:13 註冊:2004-09-27 發送簡訊給我 |
var xm,sqlstr:string; begin xm:=trim(edit1.Text ); sqlstr:='SELECT t_xsb.xm as xm,t_xsb.csny as csny,td_zydm.zymc as zymc,td_xbdm.xbmc from t_xsb '; sqlstr:=sqlstr ' inner join td_zydm on t_xsb.zydm=td_zydm.zydm'; sqlstr:=sqlstr ' inner join td_xbdm on t_xsb.xbdm=td_xbdm.xbdm'; if xm<>'' then begin xm:='%' xm '%'; sqlstr:=sqlstr ' where t_xsb.xm like ''' xm ''' '; end; query1.Close; query1.SQL.Clear ; query1.SQL.Add(sqlstr); query1.Open; end; |
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