Compose an IN for MySQL on PHP.

inQuery.php

<?php 

/**
   * Since PDO doesn't support arrays for the IN natively
   * You use the result in the SQL query string as IN($inQuery) 
   * and $inValues as the $params for the PDO function
   * ['A1' => 'first value to find', 'A2' => 'second value to find']
   *
   * @param array $toFind
   * @param string $queryVariableName
   * @return array
   */
  function getInQuery(array $toFindItems, $queryVariableName){
    $inQuery = "";
    $inValues = array();

    foreach($toFindItems as $key=>$toFindItem){
      if($inQuery){
        $inQuery .= ",";
      }
      $queryVariableNameComposed = ":".$queryVariableName.$key;
      $inQuery .= $queryVariableNameComposed;
      $inValues[$queryVariableNameComposed] = $toFindItem;
    }

    return [$inQuery, $inValues];
  }

?>