检查mysql集中是否存在值，如果是，则打印它[复制]

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• mysql_fetch_array()/mysql_fetch_assoc()/mysql_fetch_row()/mysql_num_rows etc… expects parameter 1 to be resource or result 32 answers

How would I go about trying to check if a certain value exists in a mysql set? I have this code:

that I was experimenting with (I doubted it would work) And it's throwing this error:

$result = mysql_query("SELECT * FROM posts ORDER BY time DESC");
while ($row = mysql_fetch_array($result)) {
    $result1 = mysql_query("SELECT * FROM friends WHERE friends = $row{'name'}");
    $row1 = mysql_fetch_array($result1);
    if ($row == 1) {
        echo "<b style='color: #D55292;'>".$row{'name'}."</b> says <br>".$row{'cont'}."<br><b style='color: #A1A1A1';>Posted on ".$row{'time'}."</b><br><br>";
    }
 }

I'm getting these errors:

Notice: Array to string conversion in C:\xampp\htdocs\index.php on line 44

Warning: mysql_fetch_array() expects parameter 1 to be resource, boolean given in        C:\xampp\htdocs\index.php on line 45

Notice: Array to string conversion in C:\xampp\htdocs\index.php on line 44

Warning: mysql_fetch_array() expects parameter 1 to be resource, boolean given in C:\xampp\htdocs\index.php on line 45

Notice: Array to string conversion in C:\xampp\htdocs\index.php on line 44

Warning: mysql_fetch_array() expects parameter 1 to be resource, boolean given in C:\xampp\htdocs\index.php on line 45

Could you guys give me a few pointers on how I would go about doing this? Thanks in advanced!

I just thought the question might not be clear enough:

I have a set that stores all your "friends" in my "friends" table. I also have a table that stores all the "posts" with the values of your name, the content, the time, and who can view it. I'm trying to get those posts (Which I have done successfully), and print them. I can do that. I just want to make it so you can only see posts where the "name" value is equal to a string in your "friends" set.

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Answer 1

Some PHP errors: AFAIR it's not $row{'name'} but $row['name'] and you should initiate the variable outside of the string. Same thing for $row{'cont'}

$result = mysql_query("SELECT * FROM posts ORDER BY time DESC");
while ($row = mysql_fetch_array($result)) {
    $name = $row['name'];
    $result1 = mysql_query("SELECT * FROM friends WHERE friends = '$name'");
    $row1 = mysql_fetch_array($result1);
    if ($row == 1) {
        echo "<b style='color: #D55292;'>".$row['name']."</b> says <br>".$row['cont']."<br><b style='color: #A1A1A1';>Posted on ".$row['time']."</b><br><br>";
    }
 }

I'm not sure, why do you need $result1 respectively $row1 since you don't use them in the code. A better solution would be, if you join the two tables so you wouldn't need the second query, which you execute for each post:

 $sql = "SELECT post.time, friends.name, ... 
           FROM post 
           JOIN friends on post.name = friends.name 
       ORDER BY post.time DESC";