sql query along with variable or something else?

[3_grosz]

Hi everyone

I know how to pass $_GET['id'] variable to sql query. It is like this:

	SELECT historical_epoch, picture_link, picture_title, picture_author
		FROM historical_epochs
		WHERE id = {$_GET['id'])};

and this:

	SELECT questions.id, questions.question
		FROM epochs JOIN  questions
		ON epochs.id = questions.epoch_id
		AND epochs.id = {$_GET['id'])}
		ORDER BY RAND()
		LIMIT 2;

But how to pass something else eg. 'answers.question_id = 3' to sql query? What should I do with 'answers.question_id = 3'?

	SELECT answer, boolean_type FROM questions JOIN answers
		ON questions.id=answers.question_id
		WHERE [B]answers.question_id = 3[/B] ORDER BY RAND();

Please help.

Thanks in advance for yours reply.

[dagon]

you have an erroneous ) in the query

[3_grosz]

dagon;10927355 wrote:

you have an erroneous ) in the query

I see redundant parenthesis. They aren't cause of my problem.

[dagon]

ok, i did stop reading at the first error. looking again i can't say i really see the problem.

[nkzle]

WHERE id={$_GET['id']}

should work. how are you calling the query? through print or echo ? or are you using a fetch call?

[3_grosz]

dagon;10927360 wrote:

ok, i did stop reading at the first error. looking again i can't say i really see the problem.

SELECT answer, boolean_type FROM questions JOIN answers
	ON questions.id=answers.question_id
	WHERE answers.question_id = [B]3[/B] ORDER BY RAND();

It is okey until I don't know answer to the question 3. How to change automatically this number? I want to obtain sometimes ...WHERE answers.question_id = 4... sometimes ...WHERE answers.question_id = 5... sometimes ...WHERE answers.question_id = 6... etc.

[dagon]

$foo=7;

$sql="SELECT answer, boolean_type FROM questions JOIN answers
	ON questions.id=answers.question_id
	WHERE answers.question_id = $foo ORDER BY RAND()";

$result=mysql_query($sql) or die('ERROR -- authorisation' . mysql_error());
 ...

[3_grosz]

nkzle;10927366 wrote:

WHERE id={$_GET['id']}

should work. how are you calling the query? through print or echo ? or are you using a fetch call?

I'm using fetch_assoc(). Variable $GET['id'] works. I know, but form, IMO, which pass $GET['id'] variable isn't necessary. I must only display the contents from database.

[dagon]

it gets less and less clear what you actully want.

[johanafm]

Yes, you want to retrieve data from the database. But, unless you always want to pull something specific, such as WHERE id = 3, then you will have to write code that comes up with this number "on its own". On it's own might be a random number, or through user input etc.

The $_GET['id'] comes from the URI in the address bar of the browser, such as: http://www.someplace.com/?id=3

E.g. if you create a bunch of links

<a href="http://www.someplace.com/?id=1">First</a><br/>
<a href="http://www.someplace.com/?id=2">Second</a><br/>
<a href="http://www.someplace.com/?id=10">Tenth</a><br/>

Then the user can choose what to retrieve from the database if you use $_GET['id'] as shown above.

[3_grosz]

dagon;10927381 wrote:

it gets less and less clear what you actully want.

You are right. I want this:

$displayEpoch = new DisplayEpoch($host, $username, $password, $database);

$id = $_GET['id'];

$displayEpoch->sql = "SELECT historical_epoch, picture_link, picture_title, picture_author
						FROM historical_epochs
						WHERE id = {$id};";

$question_id = rand(1, 11);  // because I have 11 questions

$displayEpoch->sql .= "SELECT questions.id, questions.question
				FROM epochs JOIN  questions
				ON epochs.id = questions.epoch_id
				AND epochs.id = {$id}
				AND questions.id = {$question_id}
				LIMIT 1;";

$displayEpoch->sql .= "SELECT answer, boolean_type
				FROM questions JOIN answers
				ON questions.id=answers.question_id
				WHERE answers.question_id = {$question_id} limit 4;";

$displayEpoch->Display();

I resolved one problem and come across on another. Such is life 🙂