Large XML file Parsing Chunk data Filetering in PHP - php

Question

I have a large XML file more than 100 MB. I am reading the file in chunks like this
$fp = fopen('large.xml', 'r');
while ($data = fread($fp, 4096)) {
The format of XML is like this
<PersonalInfo>
<UserDetail>
<FirstName>ABC</FirstName>
<Occupation>Student</Occupation>
<DateOfBirth>08/14/1999</DateOfBirth>
</UserDetail>
<CaseDetail>....</CaseDetail>
<TransactionDetail>....</TransactionDetail>
</PersonalInfo>
<PersonalInfo>
<UserDetail>
<FirstName>XYZ</FirstName>
<Occupation>Student</Occupation>
<DateOfBirth>04/25/1991</DateOfBirth>
</UserDetail>
<CaseDetail>....</CaseDetail>
<TransactionDetail>.....</TransactionDetail>
</PersonalInfo>
<PersonalInfo>
<UserDetail>
<FirstName>DEF</FirstName>
<Occupation>Teacher</Occupation>
<DateOfBirth>05/12/1984</DateOfBirth>
</UserDetail>
<CaseDetail>....</CaseDetail>
<TransactionDetail>...</TransactionDetail>
</PersonalInfo>
I want to just include those records where the Occupation TAG is "Student" and write those results to a CSV file.
I have tried the preg_match as
preg_match( "/\(.*?)\</PersonalInfo>/s", $data, $match );
to select the Tags and then look into $match but it is returning double values(repetition).

Answer 1

First check if your xml is valid with the help of following link :
http://www.xmlformatter.net/
If your xml is valid then do following :
$dom = new DOMDocument('1.0', 'UTF-8');
$dom->formatOutput = true;
#$dom->load('large.xml');
$tags = $dom->getElementsByTagName('PersonalInfo');
foreach ($tags as $destination) {
foreach($destination->childNodes as $child) {
if ($child->textContent == "Student") {
echo "Write code to create csv file";
}
}
}