Joining two foregin keys in the same table references the same primary key

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Joining two foregin keys in the same table references the same primary key
Doctrine composite primary key as well as foregin keys
How to insert record which has foregin key referenced to primary key of another table in PHP Script?
Adding a new row to a table with many foregin keys
How to fix foreign key constraint when trying to references two primary keys from the same table?
Drop a table with primary key having foregin key reference to another table

Joining two foregin keys in the same table references the same primary key

Tag : mysql , By : user183676

Date : January 12 2021, 09:11 PM

hope this fix your issue Your query is wrong either way. But the reason for getting zeros as result are probably these conditions: b.userId = u.userId and b.userId = f.followed AND f.follower = u.userId.
IF b.userId = u.userId and b.userId = f.followed then f.followed = u.userId

SELECT
count(DISTINCT b.bookId) AS booksCount,
count(br.bookId) AS reviewsCount,
(SELECT COUNT(*) FROM Followers AS f WHERE f.followed = u.userId) AS followersCount
FROM Users AS u
LEFT JOIN Books       AS b  ON b.userId  = u.userId
LEFT JOIN BooksReview AS br ON br.bookId = b.bookId 
WHERE u.userId = 'dbb21849-ccce-4af1-aa0f-6653919bf956'

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Joining two foregin keys in the same table references the same primary key , Joining , foregin , keys , same , table , references , same , primary ,

Doctrine composite primary key as well as foregin keys

Tag : development , By : Dennizzz

Date : March 29 2020, 07:55 AM

To fix the issue you can do Validate your schema - these mappings are incorrect. Either a field is a column, or it is an association. Having both mappings on the same field is not allowed:

/**
 * ilan_emlakOzellik
 *
 * @ORM\Table()
 * @ORM\Entity
 */
class ilan_emlakOzellik
{

    /**
     * @ORM\Id
     * @ORM\ManyToOne(targetEntity="ilan")
     * @ORM\JoinColumn(name="ilanId")
     */
    private $ilanId;

    /**
     * @ORM\Id
     * @ORM\ManyToOne(targetEntity="emlakOzellik")
     * @ORM\JoinColumn(name="ozellikId")
     */
    private $ozellikId;

How to insert record which has foregin key referenced to primary key of another table in PHP Script?

Tag : php , By : krs

Date : March 29 2020, 07:55 AM

I hope this helps you . You never executed the query that's supposed to return the country ID. You just set $CountryId to the SQL string. It should be:

$sql = "SELECT CountryId FROM tbl_country_master WHERE CountryName='$CountryName'";
$result = mysqli_query($con, $sql);
$row = mysqli_fetch_assoc($result);
if ($row) {
    $CountryId = $row['CountryId'];
}

$sql = "INSERT INTO tbl_state_master(StateName, Description, CountryId)
        SELECT '$StateName', '$Description', CountryId
        FROM tbl_country_master WHERE CountryName='$CountryName'";

Adding a new row to a table with many foregin keys

Tag : chash , By : Jakub Filak

Date : March 29 2020, 07:55 AM

seems to work fine I have a small problem with setting up relations between tables in entity. Basically I have three models: AppUser, Assignment and CompletedAssignment. ,
AppUserID has no value.

[Bind(Include = "ID,AssignmentID,UserID,CompletionDate")]

[Bind(Include = "ID,AssignmentID,AppUserID,CompletionDate")]

How to fix foreign key constraint when trying to references two primary keys from the same table?

Tag : mysql , By : Giles

Date : March 29 2020, 07:55 AM

wish of those help Misson: , One single foreign key has to be created for this like:

CREATE TABLE IF NOT EXISTS TestBridge2
(
TestBridgeID integer Primary key,
WorkOrder varchar(15),      
Date datetime,                  

Foreign key (WorkOrder, Date) references TestInformation2 (WorkOrder, Date)
) ENGINE = InnoDB;