在 PHP 中使用关联数组构造 UPDATE 语句 [英] Constructing UPDATE statements using associative arrays in PHP

问题描述

在 PHP 中使用关联数组构造 UPDATE 语句的最佳方法是什么?

What is the best way to construct an UPDATE statement using associative arrays in PHP?

例如，假设我有一个这样的函数:

For example, say I have a function like so:

/**
 * For update queries
 * 
 * @param string $tableName Name of the table we're wanting to update.
 * @param array $values Associative array of columns / values to update. e.g. array('name' => 'John', 'age' => 29)
 * @param array $conditions Associative array of conditions. e.g. array('user_id' => 1) equates to "WHERE user_id = 1"
 */
 public function update($tableName, $values, $conditions = array()){
      //Construct SQL
 }

到目前为止，我已经能够构建简单的 UPDATE 语句，例如:

So far, I've been able to construct simple UPDATE statements such as:

UPDATE `myTableName` SET `name` = :name, `age` = :age WHERE `user_id` = :user_id

现在我想知道:构建 WHERE 子句的最佳方法是什么?我可以研究的其他库和代码库中是否有类似的实现?例如:如何构造具有 OR 和 AND 以及 IN() 等的 WHERE 子句?

Now I'm left wondering: What is the best way to approach constructing the WHERE clause? Are there similar implementations in other libraries and code bases that I can look into? For example: How do I approach the construction of WHERE clauses that have OR and AND and IN() etc?

UPDATE example SET col = :val WHERE user_id = :user_id AND (age = :age OR name = :name)

推荐答案

public function update($tableName, $values, $conditions = array()) {
    if (empty($values)) {
        throw new Exception('Nothing to update');
    }
    $valueStrings = array();
    foreach ($values as $name => $value) {
        $valueStrings[] = $name . ' = :' . $name;
    }
    $conditionStrings = array();
    foreach ($conditions as $column => $value) {
        $conditionString = $column;
        $conditionString .= is_array($value)
            ? ('IN ("' . implode('","', $value) . '")')
            : (' = "' . $value . '"')
        ;
        $conditionStrings[] = $conditionString;
    }
    $sql = 'UPDATE ' . $tableName
        . ' SET ' . implode(', ', $valueStrings)
        . ' WHERE ' . implode(' AND ', $conditionStrings)
    ;
    // execute query
}

但实际上您应该为此使用 ORM:

But actually you should use an ORM for that:

原则 2:使用查询构建器更新查询

这篇关于在 PHP 中使用关联数组构造 UPDATE 语句的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！