PHP - Importing A Database Via Php

Haven't really used traits much and am confused whether to import other classes in the trait or the class that uses the trait (might also be an annotation question but not sure).

Must import statements (i.e. use Foo\Bar;) be included in the class or can they be included in just the trait which is used by a class?  Does it depend and if so on what?  Does having one class use another class impact the decision?  Is it okay for one trait to use another and another trait to just use the first trait or should it use both?

What is odd is I apparently must (to not get an error) import ApiProperty to the trait but doing so is not required for the class, and must import Groups, SerializedName, and Mapping in the class but doing so is not required for the trait.

Instead of just a yes/no answer, would appreciate an explanation why it is what it is.

Thanks!

<?php

namespace App\Entity\Document;
use ApiPlatform\Core\Annotation\ApiResource;
use Doctrine\ORM\Mapping as ORM;
use App\Entity\MultiTenenacy\PublicIdTenantTrait;

// Must Groups, SerializedName, Owner be imported in this class or just PublicIdTenantTrait 
// use Symfony\Component\Serializer\Annotation\Groups;
// use Symfony\Component\Serializer\Annotation\SerializedName;use 
// use App\Entity\Owner\Owner;

/**
 * @ORM\Entity()
 * @ApiResource()
 */
class Document
{
    use PublicIdTenantTrait;
}

<?php
namespace App\Entity\MultiTenenacy;

use ApiPlatform\Core\Annotation\ApiProperty;
use Doctrine\ORM\Mapping as ORM;

trait PublicIdTenantTrait
{
    use PublicIdExtendedTenantTrait;
    
    /**
     * @ORM\Id
     * @ORM\GeneratedValue(strategy="IDENTITY")
     * @ApiProperty(identifier=false)
     * @ORM\Column(type="integer")
     */
    private $id;

    public function getId(): ?int
    {
        return $this->id;
    }
}

<?php
namespace App\Entity\MultiTenenacy;

use ApiPlatform\Core\Annotation\ApiProperty;
use Symfony\Component\Serializer\Annotation\Groups;
use Symfony\Component\Serializer\Annotation\SerializedName;
use Doctrine\ORM\Mapping as ORM;

trait PublicIdExtendedTenantTrait
{
    use TenantTrait;

    /**
     * @ORM\Column(type="integer")
     * @ApiProperty(identifier=true)
     * @Groups({"tenant_entity:read"})
     * @SerializedName("id")
     */
    private $publicId;

    public function getPublicId(): ?int
    {
        return $this->publicId;
    }

    public function setPublicId(int $publicId): PublicIdTenantInterface
    {
        $this->publicId = $publicId;

        return $this;
    }

    public function generatePublicId(): PublicIdTenantInterface
    {
        $this->getOwner()->setPublicId($this);

        return $this;
    }

    public function getPublicIdTag(): string
    {
        return lcfirst((new \ReflectionClass($this))->getShortName()).'Id';
    }
}

<?php
namespace App\Entity\MultiTenenacy;

use Doctrine\ORM\Mapping as ORM;
use App\Entity\Owner\Owner;

trait TenantTrait
{
    /**
     * inversedBy performed in child where required
     * @ORM\ManyToOne(targetEntity=Owner::class)
     * @ORM\JoinColumn(nullable=false, onDelete="CASCADE")
     */
    private $owner;

    public function getOwner(): ?Owner
    {
        return $this->owner;
    }

    public function setOwner(?Owner $owner): TenantInterface
    {
        $this->owner = $owner;

        return $this;
    }
}

1    a_id               int(11)        AUTO_INCREMENT
2    a_lobecoid         int(7)    
3    a_code             varchar(30)    utf8_general_ci
4    a_omschint         varchar(60)    utf8_general_ci
5    a_beveiligingniv   int(5)
6    a_type             varchar(5)     utf8_general_ci    
7    a_assortiment      int(5)
8    a_discipline       varchar(30)    utf8_general_ci
9    a_brutoprijs       varchar(50)    utf8_general_ci    
10    a_status          varchar(5)     utf8_general_ci    
11    a_levcode         varchar(10)    utf8_general_ci
12    a_omschr_nl       varchar(60)    utf8_general_ci
13    a_omschr_fr       varchar(60)    utf8_general_ci

16158|-H|Factory installed heater|10|S|400|CCTV|45.0|E|  1829|Factory installed heater|Factory installed heater
16159|-IR|Factory installed IR LED ring|10|S|400|CCTV|50.0|E|  1829|Factory installed IR LED ring|Factory installed IR LED ring
9001|00-SBN2|Smoke box niet geaspireerd,230VAC|10|S|267|BRAND|1587.03|D|   642|Smoke box niet geaspireerd,230VAC|Smoke box pas aspiré,230VCA
9003|00-TP1|Telescopische verlengstok voor Smoke box,2,4-4,6m|10|S|267|BRAND|644.09000000000003|D|   642|Telescopische verlengstok voor Smoke box,2,4-4,6m|Rallonge téléscopique pour Smoke box,2,4-4,6m
9004|00-TP2|Telescopische verlengstok voor Smoke box,2,4-9,2m|10|S|267|BRAND|944.64999999999998|D|   642|Telescopische verlengstok voor Smoke box,2,4-9,2m|Rallonge téléscopique pour Smoke box,2,4-9,2m
12161|001-0081|Thermistor probe,rood, high temp. 0-+150°C|10|S|52|INBRAAK|136.91|D|  1731|Thermistor probe,rood, high temp. 0-+150°C|Sonde température,rouge,high temp. 0-+150°C

$upload_article_query = "LOAD DATA INFILE 'ARTIKELS.CSV'
                             INTO TABLE artikelen
                             FIELDS TERMINATED BY '|'
                             LINES TERMINATED BY '\\r\\n'
                             (a_lobecoid, a_code, a_omschint, a_beveiligingniv, a_type, a_assortiment, a_discipline, a_brutoprijs, a_status, a_levcode, a_omschr_nl, a_omschr_fr)";
$upload_article_stmt = $dbh->prepare($upload_article_query);
    
    
$upload_article_stmt->execute();

<?php
$databasehost = "localhost"; 
$databasename = "import"; 
$databasetable = "import"; 
$databaseusername="username"; 
$databasepassword = "password"; 
$fieldseparator = ","; 
$lineseparator = "\n";
$csvfile = "test.csv";

if(!file_exists($csvfile)) {
    die("File not found. Make sure you specified the correct path.");
}

try {
    $pdo = new PDO("mysql:host=$databasehost;dbname=$databasename", 
        $databaseusername, $databasepassword,
        array(
            PDO::MYSQL_ATTR_LOCAL_INFILE => true,
            PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION
        )
    );
} catch (PDOException $e) {
    die("database connection failed: ".$e->getMessage());
}

$pdo->exec("TRUNCATE TABLE `$databasetable`");

	$affectedRows = $pdo->exec("
	LOAD DATA LOCAL INFILE ".$pdo->quote($csvfile)." REPLACE INTO TABLE `$databasetable`
	FIELDS TERMINATED BY ".$pdo->quote($fieldseparator)." 
	LINES TERMINATED BY ".$pdo->quote($lineseparator)." 
	IGNORE 1 LINES");

echo "Loaded a total of $affectedRows records from this csv file.\n";

?>