PHP pDO prepared statements to insert data in Access 2007 - php

Question

I am trying to insert data from an Excel file into an Access 2007 database using PDO prepared statements. What the code is trying to do is to check if the value in the Excel sheet exists in the database and if not to add it but it doesn't do anything
Here is the code:
$conn = connect_to_impact();
//******************************************
//select statement
$select = 'SELECT < ? FROM < ?';
$select_query = $conn->prepare($select);
for ($h = 2; $h<count($clmn[0]); $h++){
$value = $clmn[0][$h];
// query execution
$select_query->execute(array($clmn[0][1], $clmn[0][1]));
$impact_no_result = $select_query->fetchAll();
//query result in multidimensional array
$impact_no_arr = impact_no_select($impact_no_result);
// create an indexed array of results
$impact_no_r = impact_no_indexed($impact_no_arr, $clmn[0][1]);
if(is_null($impact_no_r)){
$insert_impact_no = 'INSERT INTO < ? (< ?) VALUES (< ?)';
$simple_arr = [$clmn[0][1], $clmn[0][1], $value];
$insert_query = $conn->prepare($insert_impact_no);
$insert_query->execute($simple_arr);
}
// then if the value in the column is not in the indexed array insert it
elseif(!in_array($value, $impact_no_r)){
$insert_impact_no = 'INSERT INTO < ? (< ?) VALUES (< ?)';
$simple_arr = [$clmn[0][1], $clmn[0][1], $value];
$insert_query = $conn->prepare($insert_impact_no);
$insert_query->execute($simple_arr);
}
}

Answer 1

Indeed replacements cannot be used for table name and column names in PDO prepared statements. Here is the code that fixed the issueȘ
$conn = connect_to_impact();
//******************************************
//select statement
$select = "SELECT ". $clmn[0][1] . " FROM " . $clmn[0][1];
//repeat for each row the the excel sheet starting from row 2
for ($h = 2; $h<count($clmn[0]); $h++){
//take each value from each row from column A
$value = $clmn[0][$h];
// query execution
$impact_no_result = $conn->query($select);
if($impact_no_result){
$impact_no_result_ass = $impact_no_result->fetchAll();
}
//if there is no result in the select query
if($impact_no_result == false){
$insert_impact_no = "INSERT INTO ". $clmn[0][1] . "(" . $clmn[0][1] . ") " . "VALUES ('" . $value . "');";
$execute = $conn->query($insert_impact_no);
}
//if there is a result in the select query
else {
//put query result in array
$impact_no_arr = impact_no_select($impact_no_result_ass);
//if value is not in array insert it
if(!in_array($value, $impact_no_arr)){
$insert_impact_no = "INSERT INTO ". $clmn[0][1] . "(" . $clmn[0][1] . ") " . "VALUES ('" . $value . "');";
$execute = $conn->query($insert_impact_no);
}
}
}