You shouldn’t really do this but insert in a new record instead and update it that way. But, if you really need to, you can do the following: Disable enforcing FK constraints temporarily (e.g. ALTER TABLE foo WITH NOCHECK CONSTRAINT ALL) Then update your PK Then update your FKs to match the PK change Finally … Read more
The answer in Oracle is: delete from cpi where (countryid, year) in ((‘AD’, 2010), (‘AF’, 2009), (‘AG’, 1992)) It’s fairly standard SQL syntax and I think MySQL is the same.
If you create a composite primary key, on (x, y, z), PostgreSQL implements this with the help of one UNIQUE multi-column btree index on (x, y, z). In addition, all three columns are NOT NULL (implicitly), which is the main difference between a PRIMARY KEY and a UNIQUE INDEX. Besides obvious restrictions on your data, … Read more
I’ve run into this problem a couple of times. You need to override some properties: protected $primaryKey = [‘user_id’, ‘stock_id’]; public $incrementing = false; and methods (credit): /** * Set the keys for a save update query. * * @param \Illuminate\Database\Eloquent\Builder $query * @return \Illuminate\Database\Eloquent\Builder */ protected function setKeysForSaveQuery(Builder $query) { $keys = $this->getKeyName(); if(!is_array($keys)){ … Read more
Since Table2 has a composite primary key (FileID, FileType), then any reference to it must also include both columns. ALTER TABLE dbo.Table1 ADD CONSTRAINT FK_Table1_Table2 FOREIGN KEY(FileID, FileType) REFERENCES Table2(FileID, FileType) Unless you have a unique constraint/index on the Table2.FileID field (but if so: why isn’t this the PK??), you cannot create a FK relationship … Read more
I wrote this simple PHP trait to adapt Eloquent to handle composite keys: <?php namespace App\Model\Traits; // *** Adjust this to match your model namespace! *** use Illuminate\Database\Eloquent\Builder; trait HasCompositePrimaryKey { /** * Get the value indicating whether the IDs are incrementing. * * @return bool */ public function getIncrementing() { return false; } /** … Read more
From the MySQL documentation : PRIMARY KEY A unique index where all key columns must be defined as NOT NULL. If they are not explicitly declared as NOT NULL, MySQL declares them so implicitly (and silently). A table can have only one PRIMARY KEY. The name of a PRIMARY KEY is always PRIMARY, which thus … Read more
You can make an Embedded class, which contains your two keys, and then have a reference to that class as EmbeddedId in your Entity. You would need the @EmbeddedId and @Embeddable annotations. @Entity public class YourEntity { @EmbeddedId private MyKey myKey; @Column(name = “ColumnA”) private String columnA; /** Your getters and setters **/ } @Embeddable … Read more
Just for clarification: a table can have at most one primary key. A primary key consists of one or more columns (from that table). If a primary key consists of two or more columns it is called a composite primary key. It is defined as follows: CREATE TABLE voting ( QuestionID NUMERIC, MemberID NUMERIC, PRIMARY … Read more
ALTER TABLE provider ADD PRIMARY KEY(person,place,thing); If a primary key already exists then you want to do this ALTER TABLE provider DROP PRIMARY KEY, ADD PRIMARY KEY(person, place, thing);