I have this method in my db class

我的db類中有這個方法

public function query($queryString)

{

if (!$this->_connected) $this->_connectToDb(); //connect to database

$results = mysql_query($queryString, $this->_dbLink) or trigger_error(mysql_error());

return mysql_num_rows($results) > 0 ? mysql_fetch_assoc($results) : false;

}

This works great for queries that return 1 row, but how can I get an array returned something like this?

這適用於返回1行的查詢,但是如何才能獲得返回類似的數組呢?

$array[0]['name'] = 'jim'

$array[0]['id'] = 120

$array[1]['name'] = 'judith'

$array[1]['ID'] = 121

Now I know I could use a while loop to insert this data into the array like so, but I was wondering if PHP could do this with an internal function? I havn't been able to find on the docs what I'm after.

現在我知道我可以使用while循環將這些數據插入到數組中,但我想知道PHP是否可以使用內部函數執行此操作?我無法在文檔上找到我所追求的內容。

The reason I don't want to run the while within the method is because I am going to reiterate back over the array when it's returned, and I'd rather not run through the results twice (for performance reasons).

我不想在方法中運行while的原因是因為我將在返回時重復數組,並且我不想兩次運行結果(出於性能原因)。

Is there a way to do this? Do I have a problem with my general query method design?

有沒有辦法做到這一點?我的常規查詢方法設計有問題嗎?

Thank you muchly!

非常感謝你!

5 个解决方案

#1

4

public function query($queryString)

{

if (!$this->_connected) $this->_connectToDb(); //connect to database

$results = mysql_query($queryString, $this->_dbLink) or trigger_error(mysql_error());

$data = array();

while($row = mysql_fetch_assoc($results))

{

$data[] = $row;

}

return $data;

}

this will always return an array.

這將始終返回一個數組。

EDIT: I didn't read the question well. If you realy don't want to use the loop then I would do this:

編輯:我沒有很好地閱讀這個問題。如果你真的不想使用循環,那么我會這樣做:

public function query($queryString)

{

if (!$this->_connected) $this->_connectToDb(); //connect to database

return mysql_query($queryString, $this->_dbLink) or trigger_error(mysql_error());

}

then loop over it, however I would just use the loop.

然后循環它,但我只是使用循環。

#2

2

You might also want to look at the PDO extension. You can load the entire result set into an array or you can loop using foreach.

您可能還想查看PDO擴展。您可以將整個結果集加載到數組中,也可以使用foreach循環。

$db = new PDO($connection_string, $username, $password);

$result = $db->query($queryString);

foreach($result as $row) {

// do something

}

// or

$result = $db->query($queryString);

$result_array = $result->fetchAll(PDO::FETCH_ASSOC);

?>

#3

1

Most people use a while() loop in the query to do exactly what you want and then loop over the array to process it.

大多數人在查詢中使用while()循環來完成您想要的操作,然后遍歷數組來處理它。

However, you're right: it wastes memory, which could be a problem with a large dataset. An alternative is for your query method to return the resultset resource. Then your while loop can use that to fetch each row as it requires it.

但是,你是對的:它浪費了內存,這可能是一個大數據集的問題。另一種方法是讓查詢方法返回結果集資源。然后你的while循環可以使用它來獲取它所需的每一行。

To abstract that away, I would suggest another class to do that for you. Then your query call would return a new instance of that class which has the MySQL resultset resource as an instance variable and packages up the mysql_fetch_assoc() call.

為了抽象出來,我會建議另一個班為你做這件事。然后,您的查詢調用將返回該類的新實例,該實例將MySQL結果集資源作為實例變量並打包mysql_fetch_assoc()調用。

#4

0

Look at PEAR::MDB2 (Quickstart Cheatsheet). It provides lots of different functions for doing something like this. It also does not tie you down into using MySQL specific functions because it is a database abstraction layer.

看看PEAR :: MDB2(Quickstart Cheatsheet)。它提供了許多不同的功能來做這樣的事情。它也不會限制你使用MySQL特定的功能,因為它是一個數據庫抽象層。

$result = $db->queryRow($query, MDB2_FETCHMODE_ASSOC);

$ result = $ db-> queryRow($ query,MDB2_FETCHMODE_ASSOC);

There are other abstraction layers such as ADO as well.

還有其他抽象層,如ADO。

#5

0

thanks for the ideas. I have a function that returns an associative array from the sql (used in Moodle).

謝謝你的想法。我有一個函數,從sql返回一個關聯數組(在Moodle中使用)。

$results = get_records_sql($sql);

$ results = get_records_sql($ sql);

//to create a numerically indexed array:

$data = array();

foreach ($results as $row)

{

$data[] = $row;

}

return $data;

}