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How to add foreign key between 2 partitioned table?
Im trying to add foreign key between 2 partitioned table and it gives me error (there is no unique constraint matching given keys for referenced table “user”) im using postgresql v13, pgAdmin 4.26. partitioned table to normal table foreign key works, normal table to partitioned table same error as above.
How is a partitioned table created in PostgreSQL?
A partitioned table is divided into sub-tables (called partitions), which are created using separate CREATE TABLE commands. The partitioned table is itself empty. A data row inserted into the table is routed to a partition based on the value of columns or expressions in the partition key.
What is the optional partition by clause in PostgreSQL?
The optional PARTITION BY clause specifies a strategy of partitioning the table. The table thus created is called a partitioned table. The parenthesized list of columns or expressions forms the partition key for the table.
Can You truncate a table with a FOREIGN KEY constraint?
Currently I am trying to truncate tables which have foreign key constraint on Postgresql 11.3. ERROR: cannot truncate a table referenced in a foreign key constraint DETAIL: Table “xxx” references “tableA”.
Is the partitioning key part of the primary key?
The partitioning key needs to be part of the primary key. I changed the primary key to have only one column in the first table. The user_id is unique, so there is no need for a composite primary key. I changed the names of the primary keys from id to include the table name.
Is there a workaround for a FOREIGN KEY constraint?
The only solution to have a foreign key constraint is to add value to test and include it in the foreign key definition. There is no workaround for that. By the way, you should never have a table named user as that is a reserved SQL key word. I removed the partitioning logic.
Can a foreign key from another table reference the source table?
No foreign key from another table can reference the source table. The source table cannot be referenced by a foreign key in another table. So, you have to drop the constraint, partition the table and the recreate the costraint.
Is there an active primary key / foreign key relationship?
There can be no active primary key/foreign key relationship between the source table and the target table in which the target table holds the foreign key. No foreign key from another table can reference the source table. The source table cannot be referenced by a foreign key in another table.