Php 如何返回mysql表中不存在的逗号分隔值？

我正在尝试创建一个tags表来接受来自用户的新标签

我想排除像或那样插入到标记表中的常规单词

我的想法是创建一个通用单词表，并在插入新标签时排除它们

这是我如何使用php的：

//get the general words from database and convert them into ary_general

//execlude the general words from the new words and store the rest into ary_tags

//insert the ary_tags words into tags table if doesn't exist.

但在一份声明中，我希望尽我所能：

例如：

来源：do，you，think，that，programming，is，cool

tbl_general_words
do
you
that
is

结果:

---

思考、编程、酷

一句话的方法可以奏效

<?php
//needs to be configured appropriately
$conn = new PDO($dsn, $user, $password);
// fetch associative arrays, I normally use objects myself though
$conn->setAttribute(PDO::ATTR_DEFAULT_FETCH_MODE, PDO::FETCH_ASSOC);
// split the string in question into words
$wordsToTag = explode(" ", $phraseToTag);
// create a holder for the common words
$commonWords = array();
// prepare and execute the statement
$stmt = $conn->prepare("SELECT word FROM tbl_general_words");
$stmt->execute();
// add the words to the array
while($row = $stmt->fetch())
{
    $commonWords[] = $row['word'];
}
// get the words that are not common
$wordsToTag = array_diff($commonWords, $wordsToTag);
// build your SQL string
$sql = "INSERT INTO tags (tag) VALUES ";
// fore each word, we'll need a ? to hold the paramater
foreach($wordsToTag as $wordToTag)
{
    $sql .= "(?), ";
}
// remove the trailing space and trailing comma
// this could be achieved with an array and join instead if you prefer
$sql = rtrim(trim($sql), ",");
// add the words
$stmt = $conn->prepare($sql);
$stmt->execute($wordsToTag);
?>

但是，我建议将其作为一种迭代的方法，因为它更干净

<?php
// the code is the same until the adding part
$conn = new PDO($dsn, $user, $password);
$conn->setAttribute(PDO::ATTR_DEFAULT_FETCH_MODE, PDO::FETCH_ASSOC);
$wordsToTag = explode(" ", $phraseToTag);
$commonWords = array();
$stmt = $conn->prepare("SELECT word FROM tbl_general_words");
$stmt->execute();
while($row = $stmt->fetch())
{
    $commonWords[] = $row['word'];
}

$wordsToTag = array_diff($commonWords, $wordsToTag);
// prepare the statement
$stmt = $conn->prepare("INSERT INTO tags SET tag = ?");
foreach($wordsToTag as $wordToTag)
{
    // change the param and execute, because prepared statements are designed for this
    $stmt->bindParam(1, $wordToTag);
    $stmt->execute();
}
?>

创建临时表临时标签word VARCHAR100不为空； 在临时_标记中插入值“do”、“you”、“think”、“that”、“programming”、“is”、“cool”； -mysql_queryINSERT为临时_标记值，'内爆'，'，$arr_标记'； 插入标记tagColumn、someIntColumn、someStrColumn 选择temporary_tags.word，5，“字符串值” 从临时标签 左键连接tbl_general_单词在tbl_general_单词上。单词=临时标记。单词 其中tbl_general_words.word为空；

---

删除临时表临时_标记；如果每个单词都在自己的行中，而不是存储为逗号分隔的列表，则可以很容易地完成此操作。您是指源字符串还是常规表？请为tags table显示表架构为什么只有一条语句？为什么不提取要剥离的单词，如果句子中的单个单词不在该数组中，则将其添加到标记中？预处理语句的开销非常小，特别是在不使用大型数据集的情况下。如果您使用的是大型数据集，则可以创建一个预先准备好的语句，一次插入不在该数组中的所有单词。我认为这对于保存数据库请求负载来说是一个更好的主意，因为每次尝试检查标记时，我都必须选择所有常规单词。