[How to use select and insert in single query in PDO]

Insert query is there in the code . I need to place select query and an if condn

 

[How to use select and insert in single query in PDO]

I have insert in PDO. I need to write a select query before that and get the count of the rows. Based on that I must write an if condition before insert.

 

Below is my code.

<?php


$dbhost = "localhost";
$dbuser = "root";
$dbpass = "";
$dbname = "test";

function placeholder( $text, $count = 0, $separator = ',' ) {
	$result = array();

	if ($count > 0) {
		for ($x = 0; $x < $count; $x++) {
			$result[] = $text;
		}
	}

	return implode( $separator, $result );
}

$pdo = new PDO("mysql:host=$dbhost;dbname=$dbname",$dbuser,$dbpass);

$datafields = array( 'email' => '', 'var1' => '', 'var2' => '' );

$data[] = array( 'email' => 'a@mail.com', 'var1' => 'test', 'var2' => 'test2' );
$data[] = array( 'email' => 'b@mail.com', 'var1' => 'test', 'var2' => 'test2' );
$data[] = array( 'email' => 'c@mail.com', 'var1' => 'test', 'var2' => 'test2' );

$pdo->beginTransaction(); // Speed up your inserts

$insertvalues = array();

foreach ($data as $d) {
	$questionmarks[] = '(' . placeholder( '?', sizeof($d)) . ')';
	$insertvalues = array_merge( $insertvalues, array_values($d) );
}

$sql = "INSERT INTO engagements (" . implode( ',', array_keys( $datafields ) ) . ") VALUES " . implode( ',', $questionmarks);

$statement = $pdo->prepare($sql);

try {
	$statement->execute($insertvalues);
} catch(PDOException $e) {
	echo $e->getMessage();
}
$pdo->commit();