Sunday Disturb everybody, really embarrassed, but really is anxious ah ... The question about MySQL
PHP Code
$query =mysql_query ("select * from user where id={$_post[' id ']}"); while ($result =mysql_fetch_array ($query)) { echo $result [' name ']; }
This is a simple PHP query program. Now there is a problem that if $_post[' id ' is not found in the table, that is, mysql_query () cannot find the result.
The page is not showing results, but when using FF to catch the packet, it will respond with the following error:
Mysql_fetch_array (): supplied argument is not a valid MySQL result resource in./././line xx
I don't want him to give an error right now, I want to add a judgment in the program. How should I add?
I tried if ($query) if ($query! = False) if (mysql_num_rows ($query) <1) if (mysql_fetch_array ($query))
is useless.
mysql_query if the query is not found, will it return a pointer or false?
How should this judgment be written? Let's do a favor. Thank you ...
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You Var_dump (mysql_fetch_array ($query))) and look at what's going on, you don't know.
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Shouldn't be like you said.
When mysql_query () queries a matching result, a result set of type resource is returned
Returns a result set of type resource when there are no matching results
Returns False when the query is faulted
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So that's why you a.php.
You might as well put the code out, and mysql.php it.
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Not at all.
If there is an error, it is likely that your $_post[' ID ' does not fetch a value. Otherwise the error will not be reported.
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You do not use the method of post, directly with Get run mysql.php, the same ID to see what the result is
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For $query =mysql_query ("select * from user where id={$_post[' id ']}");
If $_post[' id '] does not exist, or is empty, the SQL instruction is
SELECT * from user where id=
If $_post[' ID ' is a non-digital quantity, he has said "deliberately mistaken a certain value of the query" then the SQL instruction is
SELECT * from user where id=xxx
XXX for string
Will inevitably produce a query error!
There will be text-type error messages in the event of an error, and FF will be able to see it by grasping the bag, and the FF should abandon
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Dude, you must be using Firefox! You clear the spring to see AH.
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Output SQL directly to see
