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HomeBackend DevelopmentPHP Tutorial请问,SQL语句里怎么运行PHP函数对查询的结果进行限制

请教,SQL语句里如何运行PHP函数对查询的结果进行限制?

本帖最后由 easeyoo12 于 2014-02-27 22:50:26 编辑 请各位帮帮忙,程序的作用是先执行SQL后,对查询出的结果进行显示,但是如果再查询后在进行判断显示的话分页会出问题,代码如下:
<br />$_BCACHE->cachesql('shopsearch', 'SELECT i.itemid,m.mapapimark,m.itemid FROM '.DB::table('shopitems').'  i LEFT JOIN '.DB::table('shopmessage').' m ON i.itemid=m.itemid WHERE m.mapapimark!="" ', 0, 1, $tpp, 0, 'index', 'shop');<br />$multipage = $_SBLOCK['shopsearch_multipage'];<br />$resultcount = $_SBLOCK['shopsearch_listcount'];<br />foreach($_SBLOCK['shopsearch'] as $value) {	<br />$value = $_BCACHE->getshopinfo($value['itemid']);<br /><br /><br />//商家坐标数据处理<br />$value['X_preg1'] = preg_replace('/\(/', '', $value['mapapimark']);//去除X坐标前面的括号<br />$value['storeX'] = preg_replace('/,(.*)/','',$value['X_preg1']);//去除Y坐标以及前面的逗号,只保留X坐标<br />$value['Y_preg1'] = preg_replace('/\)/', '', $value['mapapimark']);//去除Y坐标后面的括号<br />$value['storeY'] = preg_replace('/(.*),/', '',$value['Y_preg1']);//去除X坐标以及后面的逗号,只保留Y坐标<br />$value['juli'] = GetDistance($ClientY,$ClientX,$value['storeY'],$value['storeX'], 2);<br /><br />$value['juli'] = round($value['juli'],2);<br />if($value['juli'] <= $Distance){<br />	$shoplist[] = $value;	<br />}<br />}	<br />

这个是DZ里面的一段代码,我想在WHERE m.mapapimark!="" 这个语句里,调用计算函数GetDistance对查询出的mapapimark进行计算,如果计算出的结果小于$Distance,才查询出该条数据,该如何写? 先谢谢各位。
------解决方案--------------------
如果你使用的是 sqlite 数据库就可以,否则不可以
你可以书写数据库函数,也可以在结果集中过滤
------解决方案--------------------
计算建议还是在php代码里面完成,数据库计算复杂的话会影响性能
------解决方案--------------------
不解,php 计算复杂就不会影响性能了吗?

引用:
计算建议还是在php代码里面完成,数据库计算复杂的话会影响性能
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