what is the right way to include a variable in an sql statement

Question

I want to include a variable in my sql statement but it's not outputting any data. How do I include a variable correctly?

$vStyles = $wpdb->get_results( 'SELECT slug from vf_venuestyles WHERE vid = "$vid"');

The right way is to use parameters. – Gordon Linoff Aug 15 '17 at 00:37 — Gordon Linoff, Aug 15 '17 at 00:37

score 1 · Accepted Answer · answered Aug 15 '17 at 00:24

1

Change the quote marks around: $vStyles = $wpdb->get_results("SELECT slug from vf_venuestyles WHERE vid = '$vid'");

But, unless that function / class already does something magic about that, you should look into using something with proper prepared statements.

answered Aug 15 '17 at 00:24

junkfoodjunkie

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The function is part of WordPress. – Barmar Aug 15 '17 at 00:45
@junkfoodjunkie - this is exactly what I was looking for. – Raj Oct 01 '17 at 01:24

score 0 · Answer 2 · answered Aug 15 '17 at 00:24

0

The best way is to use prepared statement

$stmt = $dbh->prepare("INSERT INTO REGISTRY (name, value) VALUES (:name, :value)");
$stmt->bindParam(':name', $name);
$stmt->bindParam(':value', $value);

// insert line
$name = 'one';
$value = 1;
$stmt->execute();

answered Aug 15 '17 at 00:24

sheplu

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he's apparently using WordPress, I don't think it uses PDO. Is there a WP way to do prepared queries? – Barmar Aug 15 '17 at 00:45

score 0 · Answer 3 · answered Aug 15 '17 at 00:25

Variables only get executed if they are inside double quotes.

Simply swap your quotation marks like this:

$vStyles = $wpdb->get_results("SELECT slug from vf_venuestyles WHERE vid = '$vid'");

Or combine the query with the variable, like this, remembering to also include the secondary quotation marks:

$vStyles = $wpdb->get_results('SELECT slug from vf_venuestyles WHERE vid = '" . $vid . '"');

Hope this helps! :)

what is the right way to include a variable in an sql statement

3 Answers3