我正在使用
PHP PDO通过JSON将对象检索到iOS应用程序.
有一个包含事件对象的数据库表.它有三个字段来存储日,月和年.数据库的所有者不希望在日期字段中存储日期,这意味着我必须处理它.
有一个包含事件对象的数据库表.它有三个字段来存储日,月和年.数据库的所有者不希望在日期字段中存储日期,这意味着我必须处理它.
该应用程序发送带有参数的URL,如下所示:
http://..hidden domain./myfile.PHP?dia_inicio=16&dia_final=15&mes_inicio=11&mes_final=12&ano_inicio=2014&ano_final=2015
这意味着我正在寻找从16Nov2014到15Dec2015的活动.
$sql = 'SELECT * FROM tbagenda WHERE (dia_evento => :di AND mes_evento = :mi AND ano_evento = :ai) OR (dia_evento <= :df AND mes_evento = :mf AND ano_evento = :af) '; // use prepared statements,even if not strictly required is good practice $stmt = $dbh->prepare( $sql ); $stmt->bindParam(':di',$dia_inicio,PDO::ParaM_INT); $stmt->bindParam(':df',$dia_final,PDO::ParaM_INT); $stmt->bindParam(':mi',$mes_inicio,PDO::ParaM_INT); $stmt->bindParam(':mf',$mes_final,PDO::ParaM_INT); $stmt->bindParam(':ai',$ano_inicio,PDO::ParaM_INT); $stmt->bindParam(':af',$ano_final,PDO::ParaM_INT); // execute the query $stmt->execute(); // fetch the results into an array $result = $stmt->fetchAll( PDO::FETCH_ASSOC ); // convert to json $json = json_encode( $result ); // echo the json string echo $json
我应该如何更改我的声明以使其适用于以下日期:16Nov2014至28Nov2014(同月),16Nov2014至5Dec2014(不同月份,同年)和16Nov2014至02May2015(不同年份)?
稍后再加:
recuperar_eventos_dia.PHP?dia_inicio=11&dia_final=26&mes_inicio=11&mes_final=11&ano_inicio=2014&ano_final=2014
PHP部分:
$start = "$ano_inicio-$mes_inicio-$dia_inicio"; $end = "$ano_final-$mes_final-$dia_final"; // In the sql,concatenate the columns to make a YYYY-MM-DD date string // and cast it to a MysqL DATE type. // That makes it possible to use BETWEEN $sql = 'SELECT * FROM tbagenda WHERE STR_TO_DATE(CONCAT_WS('-',ano_evento,mes_evento,dia_evento),"%Y-%m-%d") BETWEEN :start AND :end'; // Bind and execute the statement with 2 parameters: $stmt = $dbh->prepare( $sql ); $stmt->bindParam(':start',$start,PDO::ParaM_STR); $stmt->bindParam(':end',$end,PDO::ParaM_STR); $stmt->execute(); // fetch,etc... $result = $stmt->fetchAll( PDO::FETCH_ASSOC ); // convert to json $json = json_encode( $result ); // echo the json string echo $json;
现在来自表tbagenda的截图:
解决方法
对不起,你被这个不幸的桌子结构困住了.
我建议连接表的列以形成可用的日期字符串,并通过MysqL的内置函数STR_TO_DATE()
将它们转换为日期值.对查询字符串输入值执行相同操作,以便与BETWEEN运算符进行正确的日期比较.
// Begin by concatenating the input values into single date strings YYYY-MM-DD $start = "$ano_inicio-$mes_inicio-$dia_inicio"; $end = "$ano_final-$mes_final-$dia_final"; // In the sql,concatenate the columns to make a YYYY-MM-DD date string // and cast it to a MysqL DATE type. // That makes it possible to use BETWEEN $sql = "SELECT * FROM tbagenda WHERE STR_TO_DATE(CONCAT_WS('-','%Y-%m-%d') BETWEEN :start AND :end"; // Bind and execute the statement with 2 parameters: $stmt = $dbh->prepare( $sql ); $stmt->bindParam(':start',etc... $result = $stmt->fetchAll( PDO::FETCH_ASSOC );
字符串操作将影响此查询的性能.如你所知,如果将日期存储为正确的DATE会更好,因此MysqL不需要将它们转换为比较.然后他们也可以被编入索引.
另请注意,我没有包含日期字符串的验证.在执行查询之前,您可以考虑检查它们以确保它们生成有效日期.
// strtotime() would return false for invalid date strings... if (strtotime($start) && strtotime($end)) { // The dates are valid,and so you can proceed with the query $sql = 'SELECT.....'; }