php - 如何使 PHP 中的 SQL 查询更具可读性？

Question

当 SQL 查询中的字段很长时，如何使其更具可读性？

例如：

public function findSomethingByFieldNameId($Id) {
        $sql = "SELECT field1, field2, field3 as Field3_Something, field4, field5, field6, field7, field8, field9
                      FROM table
               JOIN table2 AS TNS ON TNS.id = table.id
                      WHERE something = 1";
 return $this->db->fetchData($sql, null, 'all');
    }

Answer 1

我更喜欢 Heredoc 语法，尽管 Nowdoc 也适用于您的示例：

赫雷多克：

http://www.php.net/manual/en/language.types.string.php#language.types.string.syntax.heredoc

Nowdoc： http ://www.php.net/manual/en/language.types.string.php#language.types.string.syntax.nowdoc

两者的优点是您可以直接在该块中复制和粘贴 SQL，而无需对其进行转义或格式化。如果您需要包含解析，例如处理双引号字符串中的变量，您将使用 Heredoc。Nowdoc 的行为类似于单引号。

诺德克：

public function findSomethingByFieldNameId($Id) {
    $sql = <<<'SQL'
    SELECT field1, field2, field3 as Field3_Something, field4, field5, field6, field7, field8, field9
    FROM table
    JOIN table2 AS TNS ON TNS.id = table.id
    WHERE something = 1
SQL;

    return $this->db->fetchData($sql, null, 'all');
}

赫雷多克：

public function findSomethingByFieldNameId($Id) {
    $sql = <<<SQL
    SELECT field1, field2, field3 as Field3_Something, field4, field5, field6, field7, field8, field9
    FROM table
    JOIN table2 AS TNS ON TNS.id = table.id
    WHERE something = '$Id'
SQL;

    $sql = mysql_real_escape_string($sql);

    return $this->db->fetchData($sql, null, 'all');
}

Answer 2

您可以像这样连接它以使其更具可读性：

$sql = "SELECT field1, field2, field3 as Field3_Something,";
$sql.= " field4, field5, field6, field7, field8, field9";
$sql.= " FROM table JOIN table2 AS TNS ON TNS.id = table.id";
$sql.= " WHERE something = 1";

注意：确保在连接查询时，不要忘记在双引号之间开始新行之前留下空格，否则会出现查询无效错误

Answer 3

 $sql = "SELECT field1,
                field2,
                field3 as Field3_Something,
                field4,....
         FROM table
         JOIN table2 AS TNS ON TNS.id = table.id
         WHERE something = 1";

Answer 4

这只是另一种方式。

请注意，数组连接比字符串连接快。

$sql = join(" \n", Array(
    'SELECT ',
    '    [...fields...]',
    '    [...more fields...]',
    'FROM table',
    'JOIN table2 AS TNS ON TNS.id = table.id',
    'WHERE something = 1',
));

Answer 5

<?php
   public function findSomethingByFieldNameId($Id) {
        $sql = "SELECT 
                    field1, 
                    field2, 
                    field3 as Field3_Something, 
                    field4, 
                    field5, 
                    field6, 
                    field7, 
                    field8, 
                    field9
                FROM 
                    table
                JOIN table2 AS TNS 
                    ON TNS.id = table.id
                WHERE 
                    something = 1";
        return $this->db->fetchData($sql, null, 'all');
}
?>